Exact scaling in the expansion-modification system

This work is devoted to the study of the scaling, and the consequent power-law behavior, of the correlation function in a mutation-replication model known as the expansion-modification system. The latter is a biology inspired random substitution model for the genome evolution, which is defined on a binary alphabet and depends on a parameter interpreted as a \emph{mutation probability}. We prove that the time-evolution of this system is such that any initial measure converges towards a unique stationary one exhibiting decay of correlations not slower than a power-law. We then prove, for a significant range of mutation probabilities, that the decay of correlations indeed follows a power-law with scaling exponent smoothly depending on the mutation probability. Finally we put forward an argument which allows us to give a closed expression for the corresponding scaling exponent for all the values of the mutation probability. Such a scaling exponent turns out to be a piecewise smooth function of the parameter.Comment: 22 pages, 2 figure

Design of a large scale flow-meter test and calibration facility

The design and set up of a large-scale flowmeter calibration and test facility is presented. The facility was designed to handle flowmeters with diameters between 6” and 14”, flow rates up to 0.3 m3/s and to give results less than 1% accurate. The calibration methodology consisted firstly in calibrating the pattern flowmeters, using volume and time primary measurements, and secondly, comparing the pattern to the flowmeters needing calibration. The design and calculation of the primary calibration device is addressed, including numerical simulations of the outflow manifold and the comparison to experimental data. The calibration facility proved to be accurate and reliable in producing renewed calibration data for various tested flowmeter

Design of a flow deflector for an accurate flow meter calibration facility

The design and test of a flow deflector gate used for controlling the flow deviation toward the primary tank in a flow-meter calibration facility is presented. The deflector gate is pneumatically controlled and permits the flow conduction to either the suction tank or to the primary tank. The deflector is designed to approximately compensate the flow deficit towards the primary tank during the opening, with the flow excess while in the shutting process. Numerical simulations are performed to study the flow hydrodynamics during the deflector operation. Results are compared to experimental data, and used to improve the gate design. The enhanced design proved to guarantee the uniformity of the flow through the calibration section and the dramatic reduction of the error in volume measurement during calibration

Design of the distribution manifold for a large-scale flowmeter calibration facility

The design and test of the distribution manifold for a large-scale flowmeter calibration facility is presented. The design was intended to have an air-free flow operation and a free-surface flow-like towards the downstream half-body discharge. Back of the envelope calculations are presented for the estimation of the preliminary dimensions. Numerical simulations of the flow during manifold steady state operation are utilized to refine the manifold design. No air entrapment is noticed in the flow simulatio

Design of a large scale flow-meter test and calibration facility

The design and set up of a large-scale flowmeter calibration and test facility is presented. The facility was designed to handle flowmeters with diameters between 6” and 14”, flow rates up to 0.3 m3/s and to give results less than 1% accurate. The calibration methodology consisted firstly in calibrating the pattern flowmeters, using volume and time primary measurements, and secondly, comparing the pattern to the flowmeters needing calibration. The design and calculation of the primary calibration device is addressed, including numerical simulations of the outflow manifold and the comparison to experimental data. The calibration facility proved to be accurate and reliable in producing renewed calibration data for various tested flowmeter

Microtopography and Thickness Measurement with Digital Holographic Microscopy Highlighting and Its Tomographic Capacity

The refocusing capacity is a unique feature of digital holography. In this chapter, we show the capability of reconstructing digital holograms at different planes for different purposes. One of such purposes is to increase the focus depth of the microscope system. First, we show experimental results of the feasibility to perform digital holographic microscopy (DHM) using a Mirau interferometric objective. A profile phase comparison of a 4.2 μm high microlens using interferometry and DHM, extending the depth of focus of the microscope objective as proof of the proposal, is presented. Second, it is also useful in reducing shot noise when using an LED as a light source. In order to attain the reduction noise, we performed an averaging process of phase and amplitude images reconstructed at different reconstruction distances. This reconstruction range is performed within the focus depth of the optical system. We get a reduction of 50% shot noise. Finally, we show a strategy based on this tomographic capability of reducing a ringing effect by using an ideal filter in off‐axis digital holography

Sampling scheme analysis for estimating damage levels of Spodopfera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) in cornfield

The fall armyworm Spodopterafrugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is an important economical corn pest in Colombia. Reliable sampling procedures have been recomended for implementing pest management. However, little is know in Colombia about the sampling scheme and the number of plants per hectare required to estimate a confidence damage level in corn. Three experiments were done at the Regional Center of Investigations "Nataima" (Tolima), located at 420 m.a.s.l. and with an average temperature of 28°C, with the purpose of contribuiting in basic information for sampling fall armyworm damage in corn. The results showed that the methods of two diagonals and 50 plants per hectare were the most practical and statistically efficient, to estimate infestation levels based upon the damage caused by the first and second instar larvae.El gusano cogollero del maíz, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), es una plaga de importancia económica en Colombia. Para su manejo se recomienda efectuar muestreos de campo antes de tomar una decisión al respecto. Poco se conoce en relación con el método de muestreo más adecuado y el número de plantas requerido para estimar un nivel de daño confiable en el cultivo del maíz. Con el fin de aportar información básica en los aspectos señalados, se realizaron tres experimentos en el Centro Regional de Investigaciones "Nataima" del ICA, en Espinal (Tolima), ubicado a 420 m.s.n.m. y con una temperatura media de 28°. El análisis de regresión simple por el origen señaló que el método de muestreo consistente en 2 diagonales y el de 50 plantas/ha son los más prácticos para determinar el nivel de infestación del cogollero del maíz, basado en la variable plantas con daño inicial, es decir el ocasionado por larvas del primero y segundo instarMaíz-Zea may

The use of cosmic muons in detecting heterogeneities in large volumes

The muon intensity attenuation method to detect heterogeneities in large matter volumes is analyzed. Approximate analytical expressions to estimate the collection time and the signal to noise ratio, are proposed and validated by Monte Carlo simulations. Important parameters, including point spread function and coordinate reconstruction uncertainty are also estimated using Monte Carlo simulations.Comment: 8 pages, 11 figures, submetted to NIM

Asymptotics and zeros of Sobolev orthogonal polynomials on unbounded supports

In this paper we present a survey about analytic properties of polynomials orthogonal with respect to a weighted Sobolev inner product such that the vector of measures has an unbounded support. In particular, we are focused in the study of the asymptotic behaviour of such polynomials as well as in the distribution of their zeros. Some open problems as well as some new directions for a future research are formulated.Comment: Changed content; 34 pages, 41 reference

Physicochemical Quality, Antioxidant Capacity and Nutritional Value in Tuberous Roots of Some Wild Dahlia Species

The aim of this research was to evaluate the physicochemical quality, antioxidant capacity and nutritional value in tuberous roots of some wild dahlia species. The experiment was carried out in the Department of Plant Science of the Autonomous University Chapingo, Mexico. Plants were established in a randomized complete block design with five replications. The total soluble solids (TSS), titratable acidity (TA), vitamin C (VC), total phenols (TP), antioxidant capacity (AC), inulin and its proximate composition were evaluated. Among the materials analyzed, the most outstanding wild species were Dahlia campanulata, D. coccinea and D. brevis, where D. campanulata stood out for its concentration of VC (0.05 mg 100 g-1), AC (1.88 mg VCEAC g-1), inulin, DM and TC (72.25, 24.38 and 88.37%, respectively), however, the inulin content was similar to D. coccinea (66.17%), which was also outstanding with respect to the content of TP (1.74 mg GA g-1). Likewise, D. brevis presented the highest values of RFi (5.49%) and A (78.42%). According to our results, the tuberous roots of wild dahlia species can be used as food, as well as being a source of selection of traits of nutraceutic interest for genetic improvement