Bridging the Gap between Architecture and Engineering: a Transdisciplinary Model for a Resilient Built Environment

As the focus of environmental engineering increasingly shifts to landscape-based, decentralized solutions to energy and water; and as architecture increasingly shifts its attention to resilience, ecological connectivity and independence from centralized infrastructure, these two disciplines find themselves closer in scale than before. This paper presents a collaborative project between upper level architecture and environmental engineering students focused on the design of sustainable and integrated water systems. Critical features of transdisciplinarity included: the engagement of stakeholders in the process at multiple moments; the speculative nature of working on very distant futures, the multi-scalar requirements of the collaboration, and the expectation of balancing quantitative and qualitative performance criteria. The curriculum was successful by many measures of work quality and impact. Students reflected on expectations and outcomes at two points of the semester, providing insights on challenges and opportunities. Relying on a shared responsibility for the project and well-aligned touchpoints, rather than daily- integrated studio-format, overcomes administrative constraints, but made misalignments more evident. While initially students had higher expectations of learning about the other discipline’s role than about their own, later results clearly show many more thought they had learned more about their own discipline, and expressed more confidence on their joint work. This is an encouraging finding about the power of transdisciplinary educational experiences

Infrastruttura verde e sostenibilità urbana: multifunzionalità e resilienza per la città di Somerville

Le attuali proiezioni di rapida espansione delle aree urbane e il cambiamento climatico in atto sul nostro pianeta, presentano sfide ed opportunità per la pianificazione territoriale che guarda alle città come ambiti chiave del rapporto tra persone e natura. La pianificazione, sollecitata dalla necessità di rendere gli spazi urbani più vivibili e sani, vede nei sistemi infrastrutturali verdi (Green Infrastructure, GI) lo strumento per uno sviluppo territoriale resiliente e sostenibile. Risulta opportuno evidenziare come, in tal contesto, la nozione di sostenibilità proposta dalle GI mira a travalicare i confini dell’ambientalismo e della salvaguardia del territorio nella sua accezione più ampia, per investire ed interpellare valori e stili di vita in tutti gli ambiti della nostra quotidianità conferendo, a tali strategie, responsabilità sociali, ecologiche, economiche ancor più grandi rispetto al (solo) soddisfacimento dei bisogni primari delle persone. Da qui, la consapevolezza da parte delle amministrazioni statunitensi sulla necessità di una revisione radicale del paradigma tradizionale dell’urbanistica, ha portato molte città come Somerville in Massachusetts ad investire nelle GI come strumento multifunzionale in grado di concretizzare il concetto di triple bottom line della sostenibilità. Lo scritto riporta un approccio alla revisione della letteratura scientifica e al processo di pianificazione della GI di Somerville, avvalorandone l’efficacia attraverso la quantificazione dei benefici ambientali ed economici

Universal Quantifier Derived from AFM Analysis Links Cellular Mechanical Properties and Cell–Surface Integration Forces with Microbial Deposition and Transport Behavior

In this study, we employed AFM analysis combined with mathematical modeling for quantifying cell–surface contact mechanics and magnitude and range of cell–surface interaction forces for seven bacterial strains with a wide range of cell morphology, dimension, and surface characteristics. Comprehensive cell–surface characterization including surface charge, extracellular polymeric substance content, hydrophobicity, and cell–cell aggregation analyses were performed. Flow-through column tests were employed to determine the attachment efficiency and deposition–transport behavior of these bacterial strains. No statistically significant correlation between attachment efficiency and any single-cell surface property was identified. Single-cell characterization by atomic force microscopy (AFM) yielded the mechanical deformation and elastic modulus, penetration resistance to AFM probe penetration by cellular surface substances (CSS), range and magnitude of the repulsive–attractive intersurface forces, and geometry of each strain. We proposed and derived a universal dimensionless modified Tabor’s parameter to integrate all these properties that account for their collective behavior. Results showed that the Tabor parameter derived from AFM analysis correlated well with experimentally determined attachment efficiency (α), which therefore is able to link microscale cell–surface properties with macroscale bacterial transport behavior. Results suggested that the AFM tests performed between a single cell and a surface captured the key quantities of the interactions between the cell and the surface that dictate overall cell attachment behavior. Tabor’s parameter therefore can be potentially incorporated into the microbial transport model

Biotransformation of Two Pharmaceuticals by the Ammonia-Oxidizing Archaeon Nitrososphaera gargensis.

The biotransformation of some micropollutants has previously been observed to be positively associated with ammonia oxidation activities and the transcript abundance of the archaeal ammonia monooxygenase gene (amoA) in nitrifying activated sludge. Given the increasing interest in and potential importance of ammonia-oxidizing archaea (AOA), we investigated the capabilities of an AOA pure culture, Nitrososphaera gargensis, to biotransform ten micropollutants belonging to three structurally similar groups (i.e., phenylureas, tertiary amides, and tertiary amines). N. gargensis was able to biotransform two of the tertiary amines, mianserin (MIA) and ranitidine (RAN), exhibiting similar compound specificity as two ammonia-oxidizing bacteria (AOB) strains that were tested for comparison. The same MIA and RAN biotransformation reactions were carried out by both the AOA and AOB strains. The major transformation product (TP) of MIA, α-oxo MIA was likely formed via a two-step oxidation reaction. The first hydroxylation step is typically catalyzed by monooxygenases. Three RAN TP candidates were identified from nontarget analysis. Their tentative structures and possible biotransformation pathways were proposed. The biotransformation of MIA and RAN only occurred when ammonia oxidation was active, suggesting cometabolic transformations. Consistently, a comparative proteomic analysis revealed no significant differential expression of any protein-encoding gene in N. gargensis grown on ammonium with MIA or RAN compared with standard cultivation on ammonium only. Taken together, this study provides first important insights regarding the roles played by AOA in micropollutant biotransformation

Biotransformation of Two Pharmaceuticals by the Ammonia-Oxidizing Archaeon Nitrososphaera gargensis

[Image: see text] The biotransformation of some micropollutants has previously been observed to be positively associated with ammonia oxidation activities and the transcript abundance of the archaeal ammonia monooxygenase gene (amoA) in nitrifying activated sludge. Given the increasing interest in and potential importance of ammonia-oxidizing archaea (AOA), we investigated the capabilities of an AOA pure culture, Nitrososphaera gargensis, to biotransform ten micropollutants belonging to three structurally similar groups (i.e., phenylureas, tertiary amides, and tertiary amines). N. gargensis was able to biotransform two of the tertiary amines, mianserin (MIA) and ranitidine (RAN), exhibiting similar compound specificity as two ammonia-oxidizing bacteria (AOB) strains that were tested for comparison. The same MIA and RAN biotransformation reactions were carried out by both the AOA and AOB strains. The major transformation product (TP) of MIA, α-oxo MIA was likely formed via a two-step oxidation reaction. The first hydroxylation step is typically catalyzed by monooxygenases. Three RAN TP candidates were identified from nontarget analysis. Their tentative structures and possible biotransformation pathways were proposed. The biotransformation of MIA and RAN only occurred when ammonia oxidation was active, suggesting cometabolic transformations. Consistently, a comparative proteomic analysis revealed no significant differential expression of any protein-encoding gene in N. gargensis grown on ammonium with MIA or RAN compared with standard cultivation on ammonium only. Taken together, this study provides first important insights regarding the roles played by AOA in micropollutant biotransformation