The use of prescribed fire is expected to increase in an effort to reduce the risk of catastrophic fire, particularly at urban/forest interfaces. Fire is a well-known source of particulate matter (PM) with particle sizes Յ2.5 m (PM 2.5 ), small diameter PM known to affect climate, visibility, and human health. In this work, PM 2.5 was collected during seven first-entry burns (flaming and smoldering stages) and one maintenance burn of the Coconino National Forest. and sulfate), and 48 elements (with atomic weights between sodium and lead). The PM 2.5 contained high organic carbon levels (typically Ͼ90% by mass), commonly observed ions (K ϩ , NH 4 ϩ , and NO 3 Ϫ ) and elements (K ϩ , chlorine, sulfur, and silicon), as well as titanium and chromium. Flaming produced higher K ϩ and NH 4 ϩ levels than smoldering, and the elemental signature was more complex (20 versus 7 elements). Average organic carbon ϫ 1.4 mass fractions (Ϯ standard deviation) were lower during flaming (92 Ϯ 14%) than during smoldering (124 Ϯ 24%). The maintenance (grassland) burn produced lower particle concentrations, lower NH 4 ϩ and NO 3 Ϫ levels, and higher K and chlorine levels than did the firstentry fires.

En esta revisión se describen los principales factores que afectan la producción de pigmentos por Monascus en medio sólido, así como los diferentes residuos utilizados y aquellos potenciales remanentes regionales en México que pueden ser aprovechados en la producción de pigmentos. Los colorantes producidos por el hongo Monascus han mostrado potencial aplicación en las industrias alimentaria, cosmética, farmacéutica y textil. La producción de pigmentos por Monascus se ha llevado a cabo principalmente en cultivos en estado sólido, para lo cual el uso de residuos agroindustriales como fuente de sustrato es una alternativa real que incrementa la factibilidad económica del proceso, aunado a ser una alternativa de bajo impacto ambiental. Los factores de temperatura, pH, humedad relativa y tamaño de partícula se identificaron como los factores de mayor influencia en la producción de pigmentos. Los residuos regionales de maíz, arroz y Aloe vera son los sustratos con mayor rendimiento.

In this study, previously developed anaerobic microbial consortia capable of degrading aromatic compounds were used to develop biofilms on a natural material, coyonoxtle (Opuntia imbricata), which is abundantly available in North Mexico. The developed biofilms were evaluated for their efficiency in the biodegradation of different aromatic compounds, viz., phenol, catechol, 4‐aminobenzoic acid and p‐phenylenediamine in batch reactors. It was observed that in reactors with biofilms a more than 90 % COD removal and a concomitant production of methane could be obtained. But the rate of COD removal and methane production varied depending upon the type of biofilm used. Rumen‐derived biofilms demonstrated a lag phase of 7 to 14 days, whereas sludge‐derived biofilms exhibited a lag phase of more than three weeks. Between the biofilms from two sources, rumen‐derived biofilms showed a higher COD removal and methane production than sludge‐derived biofilms. When biofilm reactors were compared with reactors containing freely suspended consortia, it was evident that both rumen– and sludge‐derived biofilm reactors exhibited a two‐fold higher COD removal and methane production. Based on the results obtained, it can be concluded that coyonoxtle has the potential for use as a substratum.