En el presente estudio se realizó el análisis de la fracción cultivable de bacterias nitrificantes asociadas a la rizósfera de tres especies de macrófitas en humedal natural de Aguazul, Casanare. El diseño experimental se basó en la cuantificación, aislamiento y establecimiento de cultivos axénicos de bacterias litoautotróficas y heterotróficas con fenotipo BAO (oxidación de amonio a nitrito) y fenotipo NOB (oxidación de nitrito a nitrato). Una vez seleccionados los aislados bacterianos, se realizaron diversas pruebas para determinar su potencial nitrificante y posteriormente fueron caracterizados a nivel bioquímico. Fue detectada una alta proporción de bacterias nitrificantes litoautótroficas con fenotipo BAO en las muestras analizadas, y fue obtenido un grupo de aislados con diverso potencial nitrificante correspondientes a los géneros Nitrobacter sp., Pseudomonas sp, Bacillus sp., y Staphylococcus sp. Se concluye que el hábitat en estudio presenta una alta concentración de bacterias nitrificantes, y que los aislados recuperados evidencian un potencial promisorio para la evaluación y optimización de procesos de remoción biológica de nitrógeno.

The effect of the organic loading rate (OLR) on the performance and microbial composition of a two-stage UASB system treating coffee processing wastewater was assessed. The system was operated with OLR up to 18.2 g COD (L d) and effluent recirculation. Methane production and effluent characteristics were monitored. The microbial composition was examined through next-generation sequencing and qPCR from the anaerobic sludge of the first reactor (R1) operated at low and high OLR. The system showed operational stability, obtaining a maximum methane production of 2.2 L CH (L d), with a removal efficiency of COD and phenolic compounds of 84 and 73%, respectively. The performance of R1 at high OLR in steady conditions was associated with an appropriate proportion of nutrients (particularly Fe) and a marked increase of the syntrophic bacteria Syntrophus and Candidatus Cloacimonas, and acetoclastic and hydrogenotrophic methanogens, mainly Methanosaeta, Methanoculleus, Methanobacterium and Methanomassiliicoccus.

Background: In 2007, Gaynor et al. discovered a previously unidentified human polyomavirus in respiratory secretions obtained from human patients with symptoms of acute respiratory tract infection. T his new virus was designated WU polyomavirus.To investigate the frequency of it infections in GuangDong, China, We sought to describe the detection and clinical characterization of WU Polyomavirus with infection in Children.Methods: From July 2008 through June 2009, nasopharyngeal aspirates were collected from 771 child ren who were hospitalized with acute lower respiratory tract infection in Second Affiliated Hos pital of Shantou University Medical College, and 82 were asymptomatic who visited the wellb eing clinic .WU Polyomaviruses was detected by using PCR technology and was identified by using DNA sequences. All WU polyomavirus positive specimens were screened for 9 comme n viruses (influenza A and B; RSV; PIV 1 and 3; human metapneumovirus; human bocavirus; adenovirus; rhinovirus)by using PCR or RT-PCR.Results: In this study, fifteen of the 771 tested specimens with acute lower respiratory tract infection were positive fo r WU polyomavirus, the positive rate was 1.95%. and all of the asymptomatic children who vis ited the wellbeing clinic were negative. Positive specimens were noted for patients 2 months to 48 months of age, the median age was 18.8 months. Of the 15 WU Polyomaviruses positive patients, 9 (60%) were male.,6(40%) were female.WU polyomavirus was the sole virus detected in 9 spe cimens(60%) from patients with acute respiratory tract infection. WU polyomavirus were asso ciated with the coinfection of another respiratory virus in 6 of 15 (40%), most frequently with RSV (n = 4),follo wed by adenovirus (n = 1) and rhinovirus (n = 1). The most common clinical findings in the pa tients with WU polyomavirus are cough,fever, wheezing.The most frequent diagnoses were pneumonia (n = 8),bronchiolitis(n = 4), upper respiratory tract infections (n = 2) and bronchitis(n = 1).A severe case was complication with viral encephalitis.Conclusion: We suggests that WU Polyomaviruses may be a respiratory pathogen because WU polyomav irus was the sole virus detected in 9 specimens from patients with respiratory illness and all of the asymptomatic were negative.The most common clinical findings are cough and wheezing .Young children are the main target. And the pathogenetic condition are generally mild. More comprehensive studies are required to prove these viruses are agents causing respiratory disease.

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1 Resumen-En este trabajo se presenta la caracterización de macroinvertebrados que colonizan aguas de la quebrada La Calaboza (un importante sistema hídrico del departamento de Casanare), con la finalidad de determinar el estado de la calidad del agua y mejorar la comprensión de la entomofauna autóctona, en función de su respuesta a condiciones de verano e invierno. Los macroinvertebrados fueron colectados a partir de seis estaciones de muestreo e identificados a nivel de familia. Adicionalmente, se estableció su relación con diversas variables fisicoquímicas. El estado ambiental se determinó mediante la aplicación de tres índices bióticos: BMWP, ASPT y EPT. A pesar del impacto de las actividades antropogénicas, la calidad del agua de la quebrada fue catalogada como aceptable o buena. Independientemente del periodo, Ephemeróptera fue el orden predominante en la mayoría de las estaciones seleccionadas. No obstante, el periodo de invierno presentó los índices bióticos más bajos, asociado con una diferente distribución de individuos y