Search results for "characterization"

Evolution of the leucine gene cluster in Buchnera aphidicola: insights from chromosomal versions of the cluster.

2004

ABSTRACT In Buchnera aphidicola strains associated with the aphid subfamilies Thelaxinae, Lachninae, Pterocommatinae, and Aphidinae, the four leucine genes ( leuA , - B , - C , and - D ) are located on a plasmid. However, these genes are located on the main chromosome in B. aphidicola strains associated with the subfamilies Pemphiginae and Chaitophorinae. The sequence of the chromosomal fragment containing the leucine cluster and flanking genes has different positions in the chromosome in B. aphidicola strains associated with three tribes of the subfamily Pemphiginae and one tribe of the subfamily Chaitophorinae. Due to the extreme gene order conservation of the B. aphidicola genomes, the v…

Uniformization with infinitesimally metric measures

2019

We consider extensions of quasiconformal maps and the uniformization theorem to the setting of metric spaces $X$ homeomorphic to $\mathbb R^2$. Given a measure $\mu$ on such a space, we introduce $\mu$-quasiconformal maps $f:X \to \mathbb R^2$, whose definition involves deforming lengths of curves by $\mu$. We show that if $\mu$ is an infinitesimally metric measure, i.e., it satisfies an infinitesimal version of the metric doubling measure condition of David and Semmes, then such a $\mu$-quasiconformal map exists. We apply this result to give a characterization of the metric spaces admitting an infinitesimally quasisymmetric parametrization.

Caratterizzazione delle vernici da antichi strumenti musicali.

2011

Drug Activity Characterization Using One-Class Support Vector Machines with Counterexamples

2013

The problem of detecting chemical activity in drugs from its molecular description constitutes a challenging and hard learning task. The corresponding prediction problem can be tackled either as a binary classification problem (active versus inactive compounds) or as a one class problem. The first option leads usually to better prediction results when measured over small and fixed databases while the second could potentially lead to a much better characterization of the active class which could be more important in more realistic settings. In this paper, a comparison of these two options is presented when support vector models are used as predictors.

New Lignocellulosic Aristida adscensionis Fibers as Novel Reinforcement for Composite Materials: Extraction, Characterization and Weibull Distributio…

2019

In this research, the Aristida adscensionis fibers (AAFs) were taken out from the plants and its fundamental properties anlayzed for the first time. The AAFs were characterized and compared with other natural fibers by the use of physico-chemical analysis and various characterization techniques such as FT-IR, XRD, NMR, TGA, SEM and AFM. Chemical analysis showed that A. adscensionis fibers have a high cellulose content of 70.78% whereas the contents of lignin and wax are equal to 8.91% and 2.26%, respectively. The FT-IR, XRD and NMR analysis confirmed that AAFs are rich in cellulose content with CI and CS equal to 58.9% and 11.5 nm, respectively. Pycnometer analysis allowed to estimate a den…

Combined Nontargeted Analytical Methodologies for the Characterization of the Chemical Evolution of Bottled Wines

2015

Mesoscopic self-organisation of magnetic Cobalt-based nanofibers and nanoclusters in surfactant matrix

2008

A Comparative Analysis of the Electrophilicity of Organic Molecules between the Computed IPs and EAs and the HOMO and LUMO energies

2007

[EN] The electrophilicity index, omega, of a series of substituted ethylenes used in some relevant organic reactions has been evaluated from the ionization potential JP) and the electron affinity (EA) computed by vertical ionization at the B3LYP/aug-cc-PVTZ level. The corresponding electrophilicity values are well correlated with those obtained from the HOMO and LUMO energies of the neutral molecules. The good linear correlation found between omega(I,A) and omega(H,L)(LBS), and between omega(H,L)(LBS) and omega(H,L)(SBS) allows to confirm the use of the easily available B3LYP/6-31G(*) HOMO and LUMO energies to obtain reasonable values of the global electrophilicity index of organic molecule…

Inside Cover: Synthesis and Characterization of Carbazole-Linked Porphyrin Tweezers (Chem. Eur. J. 34/2015)

2015

ChemInform Abstract: Catenanes and Threaded Systems: From Solution to Surfaces

2009

Functional catenanes and threaded systems able to perform controllable mechanical motions are ideally suited for the design of molecular devices displaying mechanical, electronic, information or sensing functions. These systems have been extensively studied in solution phase and numerous examples of stimuli-driven molecular shuttles have been reported. However, for fully developing their potential applications, they must be interfaced with the macroscopic world. To achieve this objective, in the last few years catenanes and rotaxanes have been organized over surfaces in the form of chemisorbed monolayers or physisorbed monolayers, multilayers and thin films. This tutorial review summarizes …