Matter manipulation with extreme terahertz light: Progress in the enabling THz technology

Terahertz (THz) light has proven to be a fine tool to probe and control quasi-particles and collective excitations in solids, to drive phase transitions and associated changes in material properties, and to study rotations and vibrations in molecular systems. In contrast to visible light, which usually carries excessive photon energy for collective excitations in condensed matter systems, THz light allows for direct coupling to low-energy (meV scale) excitations of interest, The development of light sources of strong-field few-cycle THz pulses in the 2000s opened the door to controlled manipulation of reactions and processes. Such THz pulses can drive new dynamic states of matter, in which materials exhibit properties entirely different from that of the equilibrium. In this review, we first systematically analyze known studies on matter manipulation with strong-field few-cycle THz light and outline some anticipated new results. We focus on how properties of materials can be manipulated by driving the dynamics of different excitations and how molecules and particles can be controlled in useful ways by extreme THz light. Around 200 studies are examined, most of which were done during the last five years. Secondly, we discuss available and proposed sources of strong-field few-cycle THz pulses and their state-of-the-art operation parameters. Finally, we review current approaches to guiding, focusing, reshaping and diagnostics of THz pulses. (C) 2019 The Author(s). Published by Elsevier B.V

Nuevas estrategias para el desarrollo de biosensores ópticos aplicados al análisis de micotoxinas y hongos toxigénicos en alimentos

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Químicas, Departamento de Química Analítica, leída el 15-07-2019Mycotoxins are a diverse group of low molecular weight compounds produced as secondary metabolites by numerous species of filamentous fungi. This assemblage is chemically and toxigenically rather heterogeneous, but generally these toxins are known to cause disease and death in human and other vertebrates even at low concentrations. Mycotoxigenic fungi grow on a wide range of conditions and they can produce mycotoxins into the matrices on which they grow, often food intended for human consumption or animal feed. As a result of the ubiquitous nature of mycotoxigenic fungi, particularly in temperate and tropical regions of the world, mycotoxin contamination is often inevitable, and some calculations have estimated that approximately 25–50% of world crops are contaminated with these toxins. Although the awareness related to the hazards of mycotoxins as food and feed contaminants is growing, there are no absolute measures available for eliminating mycotoxins from agricultural products. While mycotoxin occurrence in the field can be decreased by good agronomic practices and planting resistant varieties, in the end, analytical methods capable of detecting mycotoxins and toxigenic fungi even at low concentration are of key importance for ensuring food safety...Las micotoxinas son metabolitos secundarios tóxicos producidos por algunas cepas de hongos que contaminan alimentos, especialmente cereales y hortalizas. Estos compuestos de bajo peso molecular son químicamente y toxigénicamente heterogéneos; sin embargo, muchas de estas toxinas pueden originar enfermedades, y en ocasiones la muerte, tanto en humanos como en otros vertebrados. Los hongos toxigénicos crecen en muchas condiciones muy diversas, lo que puede dar lugar a la aparición de micotoxinas en los alimentos destinados tanto al consumo humano como al animal. Los hongos toxigénicos están ampliamente distribuidos por todo el mundo, particularmente en las regiones templadas y tropicales, por lo que la contaminación natural por micotoxinas es casi inevitable. De hecho, se estima que aproximadamente el 25–50% de los cultivos mundiales están contaminados por estas toxinas, y la preocupación sobre los peligros asociados a su presencia en alimentos es cada día mayor. Actualmente, no existen alternativas viables para su eliminación en los productos agrícolas; aunque el empleo de buenas prácticas agrícolas o la plantación de variedades resistentes a los hongos, pueden ayudar a mejorar este problema. En cualquier caso, se requieren métodos analíticos sensibles y selectivos para la detección de micotoxinas y hongos toxigénicos, a bajas concentraciones, afin de garantizar la seguridad alimentaria...Depto. de Química AnalíticaFac. de Ciencias QuímicasTRUEunpu

Research and Technology Objectives and Plans Summary (RTOPS)

A compilation of the summary portion of each of the Research and Technology Operating Plans (RTOP) used for management review and control of research currently in progress throughout NASA is presented along with citations and abstracts of the RTOPs. Four indexes are included: (1) subject; (2) technical monitor; (3) responsible NASA organization; and (4) RTOP number

Research and Technology Objectives and Plans Summary (RTOPS)

This publication represents the NASA research and technology program for FY 1985. It is a compilation of the Summary portions of each of the RTOPs (Research and Technology Objectives and Plans) used for management review and control of research currently in progress throughout NASA. The RTOP summary is designed to facilitate communication and coordination among concerned technical personnel in government, in industry, and in universities. The first section containing citations and abstracts of the RTOPs is followed by four indexes: Subject, Technical Monitor, Responsible NASA Organization, and RTOP number

A cumulative index to a continuing bibliography on aeronautical engineering

This bibliography is a cumulative index to the abstracts contained in NASA-SP-7037(184) through NASA-SP-7037(195) of Aeronautical Engineering: A Continuing Bibliography. NASA SP-7037 and its supplements have been compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). This cumulative index includes subject, personal author, corporate source, foreign technology, contract, report number, and accession number indexes