Search results for "quantitative"
showing 10 items of 2409 documents
A Monte Carlo Study of Knots in Long Double-Stranded DNA Chains.
2016
We determine knotting probabilities and typical sizes of knots in double-stranded DNA for chains of up to half a million base pairs with computer simulations of a coarse-grained bead-stick model: Single trefoil knots and composite knots which include at least one trefoil as a prime factor are shown to be common in DNA chains exceeding 250,000 base pairs, assuming physiologically relevant salt conditions. The analysis is motivated by the emergence of DNA nanopore sequencing technology, as knots are a potential cause of erroneous nucleotide reads in nanopore sequencing devices and may severely limit read lengths in the foreseeable future. Even though our coarse-grained model is only based on …
A Characterization of Quintic Helices
2005
A polynomial curve of degree 5, @a, is a helix if and only if both @[email protected]^'@? and @[email protected]^'@[email protected]^''@? are polynomial functions.
Physicochemical stability of cabazitaxel containing premix solution and diluted infusion solutions
2015
Objectives This study was conducted to investigate the extended physicochemical stability of cabazitaxel containing premix solution and diluted infusion solutions in either 0.9% sodium chloride (NaCl) or 5% glucose (G5) vehicle solution. Methods A stability indicating, reverse phase, high performance liquid chromatography assay with ultraviolet detection was developed and validated. Premix solutions of cabazitaxel were prepared in the original vials. Infusion solutions were prepared in prefilled polypropylene/polyethylene (PP/PE) infusion bags (0.9% NaCl, G5) to achieve the recommended minimum and maximum cabazitaxel concentrations (0.1 mg/mL, 0.26 mg/mL). Test solutions were stored refrige…
The use of Markovian metapopulation models: a comparison of three methods reducing the dimensionality of transition matrices.
2001
The use of Markovian models is an established way for deriving the complete distribution of the size of a population and the probability of extinction. However, computationally impractical transition matrices frequently result if this mathematical approach is applied to natural populations. Binning, or aggregating population sizes, has been used to permit a reduction in the dimensionality of matrices. Here, we present three deterministic binning methods and study the errors due to binning for a metapopulation model. Our results indicate that estimation errors of the investigated methods are not consistent and one cannot make generalizations about the quality of a method. For some compared o…
Nonmonotonic Pattern Formation in Three Species Lotka-Volterra System with Colored Noise
2005
A coupled map lattice of generalized Lotka-Volterra equations in the presence of colored multiplicative noise is used to analyze the spatiotemporal evolution of three interacting species: one predator and two preys symmetrically competing each other. The correlation of the species concentration over the grid as a function of time and of the noise intensity is investigated. The presence of noise induces pattern formation, whose dimensions show a nonmonotonic behavior as a function of the noise intensity. The colored noise induces a greater dimension of the patterns with respect to the white noise case and a shift of the maximum of its area towards higher values of the noise intensity.
AN HYPERBOLIC-PARABOLIC PREDATOR-PREY MODEL INVOLVING A VOLE POPULATION STRUCTURED IN AGE
2020
Abstract We prove existence and stability of entropy solutions for a predator-prey system consisting of an hyperbolic equation for predators and a parabolic-hyperbolic equation for preys. The preys' equation, which represents the evolution of a population of voles as in [2] , depends on time, t, age, a, and on a 2-dimensional space variable x, and it is supplemented by a nonlocal boundary condition at a = 0 . The drift term in the predators' equation depends nonlocally on the density of preys and the two equations are also coupled via classical source terms of Lotka-Volterra type, as in [4] . We establish existence of solutions by applying the vanishing viscosity method, and we prove stabil…
Water Dynamics at the Solid-Liquid Interface to Unveil the Textural Features of Synthetic Nanosponges.
2020
A Fast-Field-Cycling NMR investigation was carried out on a set of polyurethane cyclodextrin nanosponges, in order to gain information on their textural properties, which have been proven to be quite difficult to assess by means of ordinary porosimetric techniques. Experiments were performed on both dry and wet samples, in order to evaluate the behavior of the “non-exchangeable” C-bound 1H nuclei, as well as the one of the mobile protons belonging to the skeletal hydroxyl groups and the water molecules. The results acquired for the wet samples accounted for the molecular mobility of water molecules within the channels of the nanosponge network, leading back to the possible pore size distrib…
Polymere acroleine. III. Mittteilung. Oximierung und quantitative Bestimmung der Aldehydgruppen
1956
Die Oximierung von Disacryl wird beschrieben. Ferner werden Bedingungen fur eine quantitative Bestimmung von Aldehydgruppen in polymeren Acroleinen mitgeteilt. Es wird festgestellt, das Disacryl und ein durch Redox-Polymerisation gewonnenes Polyacrolein etwa 65% reaktionsfahige Aldehydgruppen enthalten. Bei Polyacroleinen, die mittels Borfluorid-Atherat oder Kaliumcarbonat gewonnen wurden, betragt der Umsatz mit Hydroxylamin nur etwa 20% d. Th. The oximation reaction of disacryl is described. The conditions of a quantitative determination of aldehyde function in polymeric acroleins have been investigated. It has been shown, that disacryl and an other polyacrolein, prepared by a redox-polyme…
Clean-up and confirmation procedures for gas chromatographic determination of pesticide residues in contaminated waters. Part I
1993
The effects of sulphuric acid, potassium hydroxide and chromic acid on eleven organochlorine and ten organophosphorus pesticides were investigated. The treatments destroy some pesticides totally or partially, leave others unaltered and have a clean-up effect. These reactions can be used to confirm the presence of an identified pesticide. The clean-up extracts in the environmental samples facilitate the identification of the organochlorine and organophosphorus pesticides and their quantitative analysis. The results obtained for contaminated surface waters show the usefulness of these methods for multi-residue capillary gas chromatography without the need for other additional separative chrom…
Un estudio sobre la praxis docente del violonchelo en los conservatorios profesionales de la provincia de Valencia / A study about the practice of te…
2016
El presente estudio tiene como objetivo conocer la metodología empleada en la especialidad de violonchelo en los conservatorios de enseñanzas profesionales de la provincia de Valencia. El instrumento de recogida de la información ha sido el cuestionario y la muestra ha estado formada por 34 profesores de 22 conservatorios. Se ha empleado una metodología de complementación, tanto cualitativa como cuantitativa. Los resultados muestran que a pesar de existir algunas coincidencias en la forma y herramientas de trabajo, cada profesor aplica su propia metodología adaptada a las necesidades y características de cada alumno.