Detection of flour or farina from Triticum aestivum in macaroni by starch-gel electrophoresis of water-soluble proteins

A water-soluble protein component, A, has been found which appears without exception at a higher concentration in Triticum aestivum than in T. durum. Quantitation of A is achieved by referring the height of densitogram peak A to the height of peak B, which corresponds to a second component that is present in all varieties studied from both species. Extreme valúes of peak height ratio (PHR) in both species are tentatively established. On the basis of these valúes, the máximum and minimum possible contents of T. aestivum in a mixture are expressed as a function of PHR. All the varieties of T. aestivum studied are detected when they contribute more than 60% to the mixture. In over 90% of all possible binary combinations between varieties of T. aestivum and T. durum, the máximum proportion of undetected T. aestivum has been 30%

“Arisco” un robot social con capacidad de interaccion, motivacion y aprendizaje

ResumenEn este artículo se describe la arquitectura del robot social “Arisco” con especial atención a su sistemas de interacción, motivación, planificación y aprendizaje. Arisco es una cabeza mecatrónica con capacidad de interacción y que incluye: gran expresividad mediante gesticulación, reconocimiento y síntesis de voz, seguimiento visual, extracción de información de internet, y sistema de aprendizaje y motivación

Genealogical data of Boer and Nubian goats in Mexico

The pedigree file of the Boer and Nubian goat breeds in Mexico was constructed using the national database provided by the Asociación Mexicana de Criadores de Ganado Caprino de Registro. Field technicians routinely updated the goat national database by recording information from flocks participating in the performance-recording system. Information on animal identification number, parents, birth date, sex, breed, and farm of origin were used to undertake pedigree analyses using the ENDOG program (version 4.8). This paper presents a pedigree data file, tables and figures of characteristics of pedigree data, pedigree analyses, pedigree integrity, effective population size and genetic conservation index. The data can be used to estimate other population parameters, to monitor the genetic diversity of the Boer and Nubian goat breeds in Mexico, and also to design balanced breeding programs, maintaining genetic variation at reasonable levels and maximizing genetic progress in these populations.202

Greening an experiment for environmental chemistry: H2S capture with elemental recovery

An experiment is presented to demonstrate the production, capture, and electrochemical remediation of H2S in a closed syringe-based system. Final products are its pure constituent elements. This experiment is suitable for an environmental chemistry laboratory and it can be completed in 3- 4 h

Fractal theory and scale change effect: application for studying soil porosity

[Abstract] In this article the fractal theory and its application to soil structure and porosity is rewieved.Fractal geometry may provide a reliable description of soil structure, particularly in the case of heterogeneous soil. The rewiev illustrates how the geometry of complex porous media may be represented with simple fractal scaling models. Furthermore, three main clases of models proposed in the literature for soil porous space representation are discussed. A case study was presented based on quantitative evaluation of pore size distributions carried on nine pairs of cultivated and uncultivated neighbour located soils. The fractal approach appears to be a useful tool for understanding domains of organization as found in soil aggregates

DIVERSIDAD DE ORQUÍDEAS (Orchidaceae) EN AGROECOSISTEMAS CAFETALEROS

Coffee (Coffea arabica L.) cultivation requires environmental conditions like those found in the cloud forest, and therefore, this agroecosystem has fragmented the forest in large part of its geographic distribution. The coffee plantations managed under conditions of shade maintain conditions that have allowed the refuge and existence of great diversity, among them orchids. In this article, we present a compilation of some studies about the importance of the coffee production agroecosystems and their role in the conservation of orchids based on the species inventory and population data. At the end, the opportunities for colonization and/or recolonization of epiphytes, in general, is mentioned, where orchids are included in an important mannerEl cultivo de café (Coffea arabica L.) requiere condiciones ambientales iguales a las registradas en el bosque de niebla, y por ello este agrosistema ha fragmentado al bosque en gran parte de su distribución geográfica. Los cafetales manejados bajo condiciones de sombra mantienen condiciones que han permitido el refugio y existencia de una gran diversidad, entre ellas las orquídeas. En este trabajo, se presenta una compilación de algunos estudios sobre la importancia de los agrosistemas cafetaleros y su papel en la conservación de orquídeas basados en inventarios de especies y datos poblacionales. Al final se menciona, las oportunidades de colonización y/o recolonización de las epífitas en general donde están incluidas de manera importante las orquídea

MICROCLIMA EN CASAS SOMBRA RELACIONADO CON RETENCIÓN DE FRUTOS DE Vanilla planifolia Jacks. ex Andrews

En los últimos años el cultivo comercial de la vainilla se realiza bajo diferentes sistemas de manejo, pero con el fin de intensificar la producción, recientemente se ha promovido el uso de casas sombra

Free initial wave packets and the long-time behavior of the survival and nonescape probabilities

The behavior of both the survival S(t) and nonescape P(t) probabilities at long times for the one-dimensional free particle system is shown to be closely connected to that of the initial wave packet at small momentum. We prove that both S(t) and P(t) asymptotically exhibit the same power-law decrease at long times, when the initial wave packet in momentum representation behaves as O(1) or O(k) at small momentum. On the other hand, if the integer m becomes greater than 1, S(t) and P(t) decrease in different power-laws at long times.Comment: 4 pages, 3 figures, Title and organization changed, however the results not changed, To appear in Phys. Rev.

Análisis del entrenamiento pliométrico como trabajo de transferencia de la electroestimulación neuromuscular

Peer Reviewe

Quantum-wave evolution in a step potential barrier

By using an exact solution to the time-dependent Schr\"{o}dinger equation with a point source initial condition, we investigate both the time and spatial dependence of quantum waves in a step potential barrier. We find that for a source with energy below the barrier height, and for distances larger than the penetration length, the probability density exhibits a {\it forerunner} associated with a non-tunneling process, which propagates in space at exactly the semiclassical group velocity. We show that the time of arrival of the maximum of the {\it forerunner} at a given fixed position inside the potential is exactly the traversal time, $\tau$. We also show that the spatial evolution of this transient pulse exhibits an invariant behavior under a rescaling process. This analytic property is used to characterize the evolution of the {\it forerunner}, and to analyze the role played by the time of arrival, $3^{-1/2}\tau$, found recently by Muga and B\"{u}ttiker [Phys. Rev. A {\bf 62}, 023808 (2000)].Comment: To be published in Phys. Rev. A (2002