Academic literature on the topic 'Biomole cules'

This chapter explores the deep sea, which represents the largest, yet least-known, biome on earth. The environment is remarkably constant across the ocean floor: cold, dark water overlying soft, deep mud. While the high hydrostatic pressure is the most obvious physical feature of the deep, it is food supply from the surface that is the limiting factor for life on the abyssal plain. In temperate areas, the food input can be seasonal, providing cues for reproductive cycles. Due to the lack of food, the community of animals in the deep sea is at much lower densities than in shallow waters. Potentially there are millions of species inhabiting the deep-sea benthos; the main groups of large, mobile organisms are echinoderms, decapod crustaceans, and fish. Recent exploration using submersibles has revealed exciting 'island' habitats in the deep sea with a level of production and diversity higher than their surrounding environments.

Actualmente la base de datos de Cambridge alberga cerca de un millón cien mil estructuras cristalinas; lo cual muestra un crecimiento exponencial de la cristalografía en las últimas décadas. Dentro de estas estructuras, existen 60,000 redes Metal-Orgánicas (MOFs), las cuales incluyen a los BioMOFs, cuya relevancia consiste en usar ligantes naturales, ser de bajo costo de producción y de fácil adquisición. Debido a los enlaces de coordinación que las generan, estas estructuras pueden producir cristales con características muy puntuales, de allí el interés del escalamiento de su síntesis mediante procesos completamente industrializados. Sus características dependen de los tipos de reacciones utilizadas para su síntesis. No obstante, se han tenido avances significativos respecto a los parámetros: mezcla de solventes, mezcla de metales y ligantes, moduladores, pH, rampas de temperatura, geometrías de coordinación de los metales, entre otros. Por estas razones, en este capítulo se hace una revisión bibliográfica sobre la síntesis de los MOFs con metales de transición, ácidos carboxílicos y adenina como ligantes, y la aplicación de los mismos, como la separación de gases producidos durante el efecto invernadero. Así mismo, se mencionan los resultados obtenidos en el Centro Conjunto de Investigación en Química Sustentable (CCIQS) UAEM-UNAM y en Laboratorio de Investigación y Desarrollo de Materiales Avanzados (LIDMA) de la UAEMex, por el grupo de investigación de Estructuras Metal-Orgánicas.

Running waters reflect the character of their landscape. Landscapes influence their streams by supplying dissolved ions to the water, determining the organic matter supply to stream foodwebs, and influencing water temperature and water flows (Gregory et al. 1991, Hynes 1975). The water that feeds streams has passed over and through the vegetation, soils, and rocks of the valley. Just as urine carries the chemical imprint of metabolic activities (such as diabetes), the kinds and amounts of dissolved matter delivered to stream channels carry the signature of the valley’s parent materials and biota. Riparian (streamside) vegetation similarly regulates the balance of carbon sources to stream consumers. In valleys with sparse riparian vegetation, abundant light at the streambed allows in-stream primary production by protists and plants to dominate. Where riparian vegetation forms a canopy over the stream, leaves and needles from shrubs and trees dominate carbon supplies to consumers because low light limits contributions from in-stream primary producers (Vannote et al. 1980). Water temperature and flow are complexly determined by climatic controls (e.g., air and soil temperatures, patterns of precipitation), landscape physiography (e.g., shading of streams by valley walls), and the filter of lightabsorbing and water-transpiring riparian vegetation. Thus, streams in the desert biome of the American Southwest, with intermittent droughts and floods, high water temperatures, and abundant light, are very different habitats from the cool, dark waters of perennial streams in the temperate rain forest of the Pacific Northwest coast (Fisher 1995). Likewise, streams in the boreal forest of Alaska (and in the cold circumboreal forests of the world) take their cues from the landscape. Cold permeates the ecology of the boreal landscape and the running waters therein. The consequences of high-latitude climate on running waters are at least three: creation of ice in both terrestrial and running water systems; limited inputs of organic matter and nutrients to foodwebs; and thermal effects of low water temperatures on biological processes (Oswood 1997). For forested streams, a good case can be made for autumn as the beginning of the stream’s “fiscal” year. Autumnal leaf fall from riparian vegetation provides a major proportion of the annual energy budget to stream foodwebs.