Ordering multiple soft gluon emissions

We present an expression for the QCD amplitude for a general hard scattering process with any number of soft gluon emissions, to one-loop accuracy. The amplitude is written in two different but equivalent ways: as a product of operators ordered in dipole transverse momentum and as a product of loop-expanded currents. We hope that these results will help in the development of an all-orders algorithm for multiple emissions that includes the full colour structure and both the real and imaginary contributions to the amplitude.Comment: v4: 3 pages; 1 figure, 4 references and small clarifications added. Version accepted for publication in Physical Review Letter

Coulomb gluons and the ordering variable

We study in detail the exchange of a Coulomb (Glauber) gluon in the first few orders of QCD perturbation theory in order to shed light on their accounting to all orders. We find an elegant cancellation of graphs that imposes a precise ordering on the transverse momentum of the exchanged Coulomb gluon.Comment: 28 pages, 12 figure

El modelo Educativo de la BICU: el caso de los estudiantes afrodescendientes e indígenas en la década 2007-2016

Este estudio describe la Educación Superior de estudiantes de origen indígenas y afro descendientes en la BICU. Se realizó análisis documental y entrevista no estructurada a informantes claves dentro y fuera de esta institución educativa. El acceso para estudiar en BICU es irrestricto para toda la población indígenas afro descendiente y mestiza. Desde 2007 hasta 2016 se han matriculado 58,166 estudiantes. El 50.25% de becas corresponde a estudiantes mestizos y 49.75% entre minorías étnicas. Para el periodo 2007-2016 en la modalidad regular, el abandono global estudiantil es de 59.95%. El marco jurídico reconoce a BICU como comunitario e intercultural, sin embargo; el perfil profesional de los estudiantes indígenas y afro descendientes, no se corresponde a su cosmovisión. El modelo educativo de BICU es absorcionista de homogeneidad cultural en transición hacia comunitario e intercultural. La implementación de software traductor de lenguas nativas puede mejorar la calidad equidad educativa de los indígenas y afro descendientes. Instructores comunitarios con habilidades y competencias interculturales y pedagógicas es una buena opción para fortalecer la interculturalidad en el contexto comunitario de BICU. Sin perder su esencia BICU puede funcionar como Comunitaria e intercultural, Universidad Comunitaria y Universidad de modelo mixto. Se requiere de liderazgo e innovación organizacional socioeducativa, comprometida para alcanzar este estatus

Infrared Irradiation, an Excellent, Alternative Green Energy Source

In this chapter, attending the request by the UNESCO, Decade to Educate in the Sustainability, a green-chemical approach is offered. Thus, the most recent advances using the infrared irradiation as alternative energy source are given; this is in order to activate an organic reaction in addition to conveniently perform the extractions of secondary metabolites. It is worth noting that this manuscript is an improved extent of a review previously reported by our group. The chapter is accomplished considering two sections, displaying a comprehensive overview: in a first instance, after a deep search in the literature, a broad compilation of suitable information is presented; in a second landscape, recent unpublished results from our and other laboratories are described

In favour of layered feet. A Response to Golston.

In this response we argue that the factorial typology predicted in Martínez-Paricio & Kager (2015), which representationally relies on the existence of internally layered ternary feet, is complete and accurate. We demonstrate it does not suffer from the problematic cases of overgeneration pointed out by Golston (this issue). Additionally, we corroborate the idea that the internally layered ternary foot is a metrical representation that is typologically warranted for stress phenomena as well as for segmental and tonal metrically conditioned distributions. We suggest that Golston's claim that 'no stress system requires internally layered ternary feet' appears to be too strong and is not empirically substantiated

Study of Essential Oils Obtained from Tropical Plants Grown in Colombia

Researchers from several Colombian universities have joined efforts for over 15 years to characterize the composition and biological properties of more than a thousand samples of essential oils (EOs) obtained from aromatic plants collected during at least 30 botanical outings in different regions of Colombia. This chapter presents a brief description of essential oil extraction and chemical characterization techniques, followed by a representative list of references to publications on EO composition obtained from tropical aromatic plants that grow in Colombia. Opportunities for the development of interesting products for the pharmaceutical, cosmetics, hygiene, and food industries are illustrated with a few selected works on the evaluation of cytotoxicity, antioxidant, antiviral, antigenotoxic activities, and repellence of these essential oils

The Expression of Biodiversity in the Secondary Metabolites of Aromatic Plants and Flowers Growing in Colombia

A network of research groups has carried out a bioprospective study of Colombia’s vegetal biodiversity, with focus on aromatic plants. This chapter presents results on the chromatographic analysis of flower fragrances and essential oils obtained from vegetal material collected in botanical expeditions to various Colombian regions. Essential oils and flower fragrances are composed of volatile substances that differ greatly in polarity, functional groups, and relative amounts. The study of these complex mixtures requires special sampling and analysis techniques, described in this chapter. The large chemical diversity of the essential oil and flower fragrance constituents is a formidable characterization challenge. Typically, the number of essential oil components surpassed 50. It was rare to find an essential oil composition in which a single substance was present with a relative amount above 50%