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121.
Anca Radulescu 《Journal of statistical physics》2008,130(2):373-385
This paper adds a computational approach to a previous theoretical result illustrating how the complexity of a simple dynamical
system evolves under deformations. The algorithm targets topological entropy in the 2-dimensional family P
Q
of compositions of two logistic maps. Estimation of the topological entropy is made possible by the correspondence between
P
Q
and a subfamily of sawtooth maps P
T
, and is based on the well-known fact that the kneading-data of a map determines its entropy. A complex search for kneading-data
in P
T
turns out to be computationally fast and reliable, delivering good entropy estimates. Finally, the algorithm is used to produce
a picture of the entropy level-sets in P
Q
, as illustration to theoretical results such as Hu (Ph.D. thesis, CUNY, 1995) and Radulescu (Discrete Cont. Dyn. Syst. 19(1):139–175, 2007). 相似文献
122.
Anca Suteanu-Simulescu Alina Diana Zamfir Raluca Ica Mirela Sarbu Cristian V. A. Munteanu Florica Gadalean Adrian Vlad Flaviu Bob Dragos Catalin Jianu Ligia Petrica 《Molecules (Basel, Switzerland)》2022,27(9)
Considering the valuable information provided by glycosphingolipids as molecular markers and the limited data available for their detection and characterization in patients suffering from Type 2 diabetic kidney disease (DKD), we developed and implemented a superior method based on high-resolution (HR) mass spectrometry (MS) and tandem MS (MS/MS) for the determination of gangliosides in the urine of DKD patients. This study was focused on: (i) testing of the HR MS and MS/MS feasibility and performances in mapping and sequencing of renal gangliosides in Type 2 DM patients; (ii) determination of the changes in the urine gangliosidome of DKD patients in different stages of the disease—normo-, micro-, and macroalbuminuria—in a comparative assay with healthy controls. Due to the high resolution and mass accuracy, the comparative MS screening revealed that the sialylation status of the ganglioside components; their modification by O-acetyl, CH3COO−, O-fucosyl, and O-GalNAc; as well as the composition of the ceramide represent possible markers for early DKD detection, the assessment of disease progression, and follow-up treatment. Moreover, structural investigation by MS/MS demonstrated that GQ1d(d18:1/18:0), GT1α(d18:1/18:0) and GT1b(d18:1/18:0) isomers are associated with macroalbuminuria, meriting further investigation in relation to their role in DKD. 相似文献
123.
124.
We provide a necessary and sufficient condition under which core allocations of arbitrary TU-games treat substitute players equally. The core satisfies the equal treatment property if and only if no player needs the participation of all of her substitutes to attain her core payoffs. We show how, without the requirement of a large number of players, this condition generalizes and unifies other sufficient conditions proposed in the literature (in the context of large games and economies) and it helps derive new results for particular classes of games. 相似文献
125.
126.
Anca Visinescu 《Physics letters. A》1994,190(5-6):425-428
The three soliton contribution to the specific heat of a classical easy-plane ferromagnet chain is calculated using asymptotic methods from the theory of differential equations depending on a large parameter. 相似文献
127.
Simona M. Coman Anca Dobre Mircea D. Banciu Aurica Petride Valentin Cimpeanu Georges Poncelet Vasile I. Parvulescu 《Journal of molecular catalysis. A, Chemical》2004,220(2):257-265
Ru–BEA catalysts with 1.0–2.5 wt.% Ru were prepared by ion exchange. The acidic properties of these catalysts were investigated using deuterated acetonitrile, pyridine, and 2,6-di-tert-butyl-pyridine. The deposited Ru was studied by CO-FTIR spectroscopy. The materials were tested as catalysts in the hydrogenation of a conjugated cyclic keto–enol, namely, 5-hydroxymethylene-5H-6,7-dihydrodibenzo[a,c]cyclohepten-6-one. Beside hydrogenation, hydrogenolysis products were identified by GC–MS and 1H NMR techniques. Relations were sought between the selectivity and some physicochemical properties of the catalyst. 相似文献
128.
129.
In the present work, we investigated the effect of an intense non-resonant laser field on the electronic structure and the nonlinear optical properties (the light absorption, the optical rectification) of a GaAs asymmetric double quantum dot under a strong probe field excitation. The calculations were performed within the compact-density matrix formalism under the steady state conditions with the use of the effective mass approximation. The obtained results show that: (i) the electronic structure and, consequently, the optical properties are sensitive to the dressed potential; (ii) the changes in the incident light polarisation lead to blue or redshifts in the intraband optical absorption spectrum; (iii) for specific values of the structure parameters and under an intense laser illumination, the asymmetric double quantum dots can be a good candidate for NOR emission of THz radiation. 相似文献
130.
Artificial metalloenzymes, based on the incorporation of a catalytically active organometallic moiety within a host protein, lie at the interface between organometallic and enzymatic catalysis. In terms of activity, reaction repertoire, substrate range and operating conditions, they take advantage of the versatility of the organometallic chemistry. In contrast, the enantioselectivity is determined by the biomolecular scaffold, which provides a well defined second coordination sphere to the organometallic moiety, reminiscent of enzymes. The attractive feature of such systems is their optimization potential, which combines chemical and genetic methods (i.e. chemogenetic) to screen diversity space. This feature article describes the implementation of such an optimization protocol for artificial transfer hydrogenases, for which we have the most detailed understanding. 相似文献