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991.
Exequiel E. Barrera Guisasola Marcelo F. Masman Ricardo D. Enriz Ana M. Rodríguez 《Central European Journal of Chemistry》2010,8(3):566-575
The potential energy surface (PES) of tyrosyl-glycyl-glycine (YGG) tripeptide in solution was explored using EDMC (Electrostatically
Driven Monte Carlo) and in the gas-phase by means of ab initio quantum chemical calculations. The theoretical computational
analysis revealed that this tripeptide possesses a significant molecular flexibility. A C7 backbone conformation was the most energetically preferred for the central Gly residue, using both methodologies. Some new
stable conformers that have not been previously reported were identified in the gas phase as well. This study points out the
interplay of backbone and side-chain contributions in determining the relative stabilities of energy minima. In addition,
the peptide backbone of YGG was compared with other small peptides containing aromatic side-chains (Phe-Gly-Gly and Trp-Gly-Gly).
The comparison with experimental X-ray results was also satisfactory.
相似文献
992.
993.
Marcelo Fernando Kern Simone de Faria Maraschin Débora Vom Endt Augusto Schrank Marilene Henning Vainstein Giancarlo Pasquali 《Applied biochemistry and biotechnology》2010,160(7):1933-1946
The chit1 gene from the entomopathogenic fungus Metarhizium anisopliae, encoding the endochitinase CHIT42, was placed under the control of the CaMV 35S promoter, and the resulting construct was
transferred to tobacco. Seventeen kanamycin-resistant transgenic lines were recovered, and the presence of the transgene was
confirmed by polymerase chain reactions and Southern blot hybridization. The number of chit1 copies was determined to be varying from one to four. Copy number had observable effects neither on plant growth nor development.
Substantial heterogeneity concerning production of the recombinant chitinase, and both general and specific chitinolytic activities
were detected in leaf extracts from primary transformants. The highest chitinase activities were found in plants harboring
two copies of chit1 inserts at different loci. Progeny derived from self-pollination of the primary transgenics revealed a stable inheritance
pattern, with transgene segregation following a mendelian dihybrid ratio. Two selected plants expressing high levels of CHIT42
were consistently resistant to the soilborne pathogen Rhizoctonia solani, suggesting a direct relationship between enzyme activity and reduction of foliar area affected by fungal lesions. To date,
this is the first report of resistance to fungal attack in plants mediated by a recombinant chitinase from an entomopathogenic
and acaricide fungus. 相似文献
994.
Marcelo Castier 《Fluid Phase Equilibria》2011,301(1):105-109
A new algorithm to find the saturation conditions of a pure substance or mixture of specified entropy is proposed. An interesting aspect is that the type of saturation point, whether a dew or bubble point, is a priori unknown. This poses particular challenges to providing good initial estimates that ensure numerical convergence of the phase equilibrium equations. A safe initialization procedure is proposed. The examples show applications of the model to computations with pure methane, pure carbon dioxide, natural gas, and contaminated carbon dioxide. The algorithm succeeds in determining the saturation condition in all of these cases. 相似文献
995.
Maxime Guitet Pinglu Zhang Dr. Filipa Marcelo Coralie Tugny Prof. Jesús Jiménez‐Barbero Dr. Olivier Buriez Prof. Christian Amatore Dr. Virginie Mouriès‐Mansuy Dr. Jean‐Philippe Goddard Prof. Louis Fensterbank Dr. Yongmin Zhang Dr. Sylvain Roland Dr. Mickaël Ménand Prof. Matthieu Sollogoub 《Angewandte Chemie (International ed. in English)》2013,52(28):7213-7218
996.
Prof. Dr. Norberto Garcia‐Cairasco Prof. Dr. Miguel Moyses‐Neto Flavio Del Vecchio José A. C. Oliveira Francisco L. dos Santos Dr. Olagide W. Castro Dr. Gabriel M. Arisi Prof. Dr. Márcio Dantas Dr. Ruither O. G. Carolino Prof. Dr. Joaquim Coutinho‐Netto Dr. Andre L. A. Dagostin Dr. Marcelo C. A. Rodrigues Prof. Dr. Ricardo M. Leão Dr. Samir A. P. Quintiliano Prof. Dr. Luiz F. Silva Jr. Prof. Dr. Leonardo Gobbo‐Neto Prof. Dr. Norberto P. Lopes 《Angewandte Chemie (International ed. in English)》2013,52(49):12747-12747
997.
Felipe A. C. Viana Raphael T. Haftka Layne T. Watson 《Journal of Global Optimization》2013,56(2):669-689
Surrogate-based optimization proceeds in cycles. Each cycle consists of analyzing a number of designs, fitting a surrogate, performing optimization based on the surrogate, and finally analyzing a candidate solution. Algorithms that use the surrogate uncertainty estimator to guide the selection of the next sampling candidate are readily available, e.g., the efficient global optimization (EGO) algorithm. However, adding one single point at a time may not be efficient when the main concern is wall-clock time (rather than number of simulations) and simulations can run in parallel. Also, the need for uncertainty estimates limits EGO-like strategies to surrogates normally implemented with such estimates (e.g., kriging and polynomial response surface). We propose the multiple surrogate efficient global optimization (MSEGO) algorithm, which adds several points per optimization cycle with the help of multiple surrogates. We import uncertainty estimates from one surrogate to another to allow use of surrogates that do not provide them. The approach is tested on three analytic examples for nine basic surrogates including kriging, radial basis neural networks, linear Shepard, and six different instances of support vector regression. We found that MSEGO works well even with imported uncertainty estimates, delivering better results in a fraction of the optimization cycles needed by EGO. 相似文献
998.
We prove that if A is an artin algebra, G is a finite group acting on A such that |G| is invertible in A, and R = A[G]b is a basic algebra associated with the skew group algebra, then A is left supported (or right supported, or laura, or left glued, or right glued, or weakly shod, or shod) if and only if so is R. 相似文献
999.
Thaís Ramos Dal Molin Gssica Domingos da Silveira Gabriela Camera Leal Larissa Sabo Müller Diana Tomazi Muratt Leandro Machado de Carvalho Carine Viana 《Biomedical chromatography : BMC》2019,33(11)
The extent of adulteration of dietary supplements has significantly increased in recent years. This situation worries health authorities and requires auxiliary analytical tools for the investigation of illegal substances purposely added. Ion exchange chromatography with conductivity detection is a consolidated analytical technique for the determination of inorganic compounds in various matrices. This technique has been applied to the pharmaceutical characterization of mainly impurities and degradation products. This work presents a new approach to ion exchange chromatography as a screening method to investigate the presence of amfepramone, femproporex, sibutramine, bisacodyl and amiloride in dietary supplements advertised for weight loss. The method was optimized and validated using a Metrosep C4 100/4.0 cation exchange column. The mobile phase consisted of 1.8 mm HNO3 containing 2% acetonitrile (v/v), with a flow rate of 0.9 ml min?1, and nonsuppressed conductivity detection was applied. The limits of detection and quantification varied from 1.01 to 3.62 mg L?1 and from 1.48 to 8.72 mg L?1, respectively. The proposed method was successful applied to 78 solid dietary supplement samples, in two of which adulterations were found. Moreover, ion exchange chromatography with conductivity detection could be easily used for quality control without prior complex sample pre‐treatment. 相似文献
1000.
R.L. Viana S.R. Lopes I.L. Caldas J.D. Szezech Z. Guimarães-Filho G.Z. dos Santos Lima P.P. Galuzio A.M. Batista Yu. Kuznetsov I.C. Nascimento 《Communications in Nonlinear Science & Numerical Simulation》2012,17(12):4690-4699
Turbulence is one of the key problems of classical physics, and it has been the object of intense research in the last decades in a large spectrum of problems involving fluids, plasmas, and waves. In order to review some advances in theoretical and experimental investigations on turbulence a mini-symposium on this subject was organized in the Dynamics Days South America 2010 Conference. The main goal of this mini-symposium was to present recent developments in both fundamental aspects and dynamical analysis of turbulence in nonlinear waves and fusion plasmas. In this paper we present a summary of the works presented at this mini-symposium. Among the questions to be addressed were the onset and control of turbulence and spatio-temporal chaos. 相似文献