Meta-omics approaches to understand and improve wastewater treatment systems

Biological treatment of wastewaters depends on microbial processes, usually carried out by mixed microbial communities. Environmental and operational factors can affect microorganisms and/or impact microbial community function, and this has repercussion in bioreactor performance. Novel high-throughput molecular methods (metagenomics, metatranscriptomics, metaproteomics, metabolomics) are providing detailed knowledge on the microorganisms governing wastewater treatment systems and on their metabolic capabilities. The genomes of uncultured microbes with key roles in wastewater treatment plants (WWTP), such as the polyphosphate-accumulating microorganism Candidatus Accumulibacter phosphatis, the nitrite oxidizer Candidatus Nitrospira defluvii or the anammox bacterium Candidatus Kuenenia stuttgartiensis are now available through metagenomic studies. Metagenomics allows to genetically characterize full-scale WWTP and provides information on the lifestyles and physiology of key microorganisms for wastewater treatment. Integrating metagenomic data of microorganisms with metatranscriptomic, metaproteomic and metabolomic information provides a better understanding of the microbial responses to perturbations or environmental variations. Data integration may allow the creation of predictive behavior models of wastewater ecosystems, which could help in an improved exploitation of microbial processes. This review discusses the impact of meta-omic approaches on the understanding of wastewater treatment processes, and the implications of these methods for the optimization and design of wastewater treatment bioreactors.Research was supported by the Spanish Ministry of Education and Science (Contract Project CTQ2007-64324 and CONSOLIDER-CSD 2007-00055) and the Regional Government of Castilla y Leon (Ref. VA038A07). Research of AJMS is supported by the European Research Council (Grant 323009

A Cultural–Historical model to inform culturally responsive Pedagogies: Case studies of educational practices in Solomon Islands and Australia

The goal of education is often considered to be emancipation and empowerment. Yet, the capacity for education to emancipate and empower can be hindered when approaches and assumptions are not shared by all the participants in an education context. This is particularly true in contexts where one set of cultural assumptions and traditions have been forced onto another, such as in the process of colonisation. This chapter provides case studies of two contexts where colonisation has had an impact on the approaches to education: in an Indigenous community in Yamatji Country in Western Australia and another in Temotu Province in Solomon Islands. In both contexts, European-heritage approaches to learning have been forced onto Indigenous cultures with little understanding of, or cultural responsiveness to, the Indigenous communities themselves. These case studies are presented through the lens of Hedegaard’s (2009) model of perspectives, with the aim of illustrating why the approach used in one context has been achieved in a more culturally responsive manner than the other. Through adaptations to the model itself, this chapter seeks to explain how two educational approaches may be successful or unsuccessful in incorporating Indigenous traditions and knowledge. The descriptive power of the model also allows us to reconceptualise these existing tensions and reimagine more responsive future adaptations. We explore the utility of the adapted model for articulating the assumptions and approaches at play, and for providing potential ways forward. These ways forward facilitate a re-imagination of education as something more than mere preparation of children for workforce participation. We argue that the model proffers ways to provide equal respect for, and emphasis on, different cultures and traditions. It also provides ways to document and understand different cultures, with scope to learn from them in our endeavour to improve educational provision. In a world where the functionalist push to improve education is globalising and frequently silences or overlooks local knowledge, the authors contend that local communities should be central rather than peripheral to the curriculum. When this occurs, it is possible to reimagine ways in which pedagogy can emancipate and empower all members of the society

Bacterial community structure corresponds to performance during cathodic nitrate reduction

Microbial fuel cells (MFCs) have applications other than electricity production, including the capacity to power desirable reactions in the cathode chamber. However, current knowledge of the microbial ecology and physiology of biocathodes is minimal, and as a result more research dedicated to understanding the microbial communities active in cathode biofilms is required. Here we characterize the microbiology of denitrifying bacterial communities stimulated by reducing equivalents generated from the anodic oxidation of acetate. We analyzed biofilms isolated from two types of cathodic denitrification systems: (1) a loop format where the effluent from the carbon oxidation step in the anode is subjected to a nitrifying reactor which is fed to the cathode chamber and (2) an alternative non-loop format where anodic and cathodic feed streams are separated. The results of our study indicate the superior performance of the loop reactor in terms of enhanced current production and nitrate removal rates. We hypothesized that phylogenetic or structural features of the microbial communities could explain the increased performance of the loop reactor. We used PhyloChip with 16S rRNA (cDNA) and fluorescent in situ hybridization to characterize the active bacterial communities. Our study results reveal a greater richness, as well as an increased phylogenetic diversity, active in denitrifying biofilms than was previously identified in cathodic systems. Specifically, we identified Proteobacteria, Firmicutes and Chloroflexi members that were dominant in denitrifying cathodes. In addition, our study results indicate that it is the structural component, in terms of bacterial richness and evenness, rather than the phylogenetic affiliation of dominant bacteria, that best corresponds to cathode performance. © 2010 International Society for Microbial Ecology All rights reserved

Evolutionary characterization of lung adenocarcinoma morphology in TRACERx

Lung adenocarcinomas (LUADs) display a broad histological spectrum from low-grade lepidic tumors through to mid-grade acinar and papillary and high-grade solid, cribriform and micropapillary tumors. How morphology reflects tumor evolution and disease progression is poorly understood. Whole-exome sequencing data generated from 805 primary tumor regions and 121 paired metastatic samples across 248 LUADs from the TRACERx 421 cohort, together with RNA-sequencing data from 463 primary tumor regions, were integrated with detailed whole-tumor and regional histopathological analysis. Tumors with predominantly high-grade patterns showed increased chromosomal complexity, with higher burden of loss of heterozygosity and subclonal somatic copy number alterations. Individual regions in predominantly high-grade pattern tumors exhibited higher proliferation and lower clonal diversity, potentially reflecting large recent subclonal expansions. Co-occurrence of truncal loss of chromosomes 3p and 3q was enriched in predominantly low-/mid-grade tumors, while purely undifferentiated solid-pattern tumors had a higher frequency of truncal arm or focal 3q gains and SMARCA4 gene alterations compared with mixed-pattern tumors with a solid component, suggesting distinct evolutionary trajectories. Clonal evolution analysis revealed that tumors tend to evolve toward higher-grade patterns. The presence of micropapillary pattern and ‘tumor spread through air spaces’ were associated with intrathoracic recurrence, in contrast to the presence of solid/cribriform patterns, necrosis and preoperative circulating tumor DNA detection, which were associated with extra-thoracic recurrence. These data provide insights into the relationship between LUAD morphology, the underlying evolutionary genomic landscape, and clinical and anatomical relapse risk.</p

Nitrogen removal with the anaerobic ammonium oxidation process

Item does not contain fulltex