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1.
Global Health ; 15(1): 85, 2019 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-31847865

RESUMEN

BACKGROUND: Localisation is a pervasive challenge in achieving sustainable development. Contextual particularities may render generalized strategies to achieve the Sustainable Development Goals (SDGs) unfeasible, impractical, or ineffective. Furthermore, many localities are resource- and data-poor, limiting applicability of the global SDG indicator framework. Tools to enable local actors to make sense of complex problems, communicate this understanding, and act accordingly hold promise in their ability to improve results. AIM: Systems approaches can help characterise local causal systems, identify useful leverage points, and foster participation needed to localise and catalyse development action. Critically, such efforts must be deeply rooted in place, involving local actors in mapping decision-processes and causation within local physical, social and policy environments. Given that each place has a unique geographical or spatial extent and therein lies its unique characters and problems, we term these activities "placially explicit." We describe and reflect on a process used to develop placially explicit, systems-based (PESB) case studies on issues that intersect with and impact urban health and wellbeing, addressing the perspectives of various actors to produce place-based models and insights that are useful for SDG localisation. METHODS: Seven case studies were co-produced by one or more Partners with place-based knowledge of the case study issue and a Systems Thinker. In each case, joint delineation of an appropriate framing was followed by iterative dialogue cycles to uncover key contextual factors, with attention to institutional and societal structures and paradigms and the motivations and constraints of other actors. Casual loop diagrams (CLDs) were iteratively developed to capture complex narratives in a simple visual way. RESULTS: Case study development facilitated transfer of local knowledge and development of systems thinking capacity. Partners reported new insights, including a shifting of problem frames and corresponding solution spaces to higher systems levels. Such changes led partners to re-evaluate their roles and goals, and thence to new actions and strategies. CLD-based narratives also proved useful in ongoing communications. CONCLUSION: Co-production of PESB case studies are a useful component of transdisciplinary toolsets for local SDG implementation, building the capacity of local actors to explore complex problems, identify new solutions and indicators, and understand the systemic linkages inherent in SDG actions across sectors and scales.


Asunto(s)
Desarrollo Sostenible , Análisis de Sistemas , Estudios de Casos y Controles , Humanos
2.
Environ Sci Technol ; 49(1): 498-503, 2015 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-25454582

RESUMEN

Understanding the parameters that drive E1 degradation is necessary to improve existing wastewater treatment systems and evaluate potential treatment options. Organic matter quality could be an important parameter. Microbial communities grown from activated sludge seeds using different dissolved organic matter sources were tested for E1 degradation rates. Synthetic wastewater was aged, filter-sterilized, and used as a carbon and energy source to determine if recalcitrant organic carbon enhances E1 degradation. Higher E1 degradation was observed by biomass grown on 8 d old synthetic wastewater compared to biomass grown on fresh synthetic wastewater (P = 0.033) despite much lower concentrations of bacteria. Minimal or no E1 degradation was observed in biomass grown on 2 d old synthetic wastewater. Organic carbon analyses suggest that products of cell lysis or microbial products released under starvation stress stimulate E1 degradation. Additional water sources were also tested: lake water, river water, and effluents from a municipal wastewater treatement plant and a treatment wetland. E1 degradation was only observed in biomass grown in treatment effluent. Nitrogen, dissolved organic carbon, and trace element concentrations were not causative factors for E1 degradation. In both experiments, spectrophotometric analyses reveal degradation of E1 is associated with microbially derived organic carbon but not general recalcitrance.


Asunto(s)
Bacterias/metabolismo , Biomasa , Estrona/metabolismo , Compuestos Orgánicos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Carbono/metabolismo , Filtración , Agua Dulce , Nitrógeno , Aguas del Alcantarillado , Factores de Tiempo , Aguas Residuales
3.
Environ Sci Technol ; 47(21): 12359-65, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24117277

RESUMEN

The effects of organic carbon concentrations and loading on the degradation of estrone (E1) were examined under various conditions in batch reactors and membrane-coupled bioreactors (MBRs). Experiments examined effects on individual microorganisms (substrate competition and growth) and on the whole community (selection). Substrate competition with organic carbon (competitive inhibition and catabolic repression) was not a factor in E1 degradation (P = 0.19 and 0.29 for two different analyses). Conversely, addition of organic carbon increased E1 degradation rates, attributable to biomass growth in feast-famine reactors over a five-day period (P = 0.016). Subsequently, however, community dynamics controlled E1 degradation rates, with other organisms outcompeting E1 degraders. More moderate but sustained increases in E1 degradation rates were observed under starvation conditions. Low influent organic carbon strength was detrimental to E1 degradation in MBRs, where organic carbon concentration and loading were decoupled (P = 0.018). These results point to the importance of multiple substrate utilizers in E1 degradation. They also suggest that while initial growth of biomass depends on the presence of sufficient organic carbon, further enrichment under starvation conditions may improve E1 degradation capability via the growth and/or stimulation of multiple substrate utilizers rather than heterotrophs characterized by an r-strategist growth regime.


Asunto(s)
Carbono/farmacología , Estrona/análisis , Compuestos Orgánicos/farmacología , Bacterias/efectos de los fármacos , Bacterias/genética , Biodegradación Ambiental/efectos de los fármacos , Biodiversidad , Análisis de la Demanda Biológica de Oxígeno , Biomasa , Reactores Biológicos/microbiología , ADN Espaciador Ribosómico/genética , Eliminación de Residuos Líquidos
4.
Environ Sci Technol ; 45(22): 9543-9, 2011 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-21981654

RESUMEN

In this study, the impact of tertiary-treated municipal wastewater on the quantity of several antibiotic resistance determinants in Duluth-Superior Harbor was investigated by collecting surface water and sediment samples from 13 locations in Duluth-Superior Harbor, the St. Louis River, and Lake Superior. Quantitative PCR (qPCR) was used to target three different genes encoding resistance to tetracycline (tet(A), tet(X), and tet(W)), the gene encoding the integrase of class 1 integrons (intI1), and total bacterial abundance (16S rRNA genes) as well as total and human fecal contamination levels (16S rRNA genes specific to the genus Bacteroides ). The quantities of tet(A), tet(X), tet(W), intI1, total Bacteroides , and human-specific Bacteroides were typically 20-fold higher in the tertiary-treated wastewater than in nearby surface water samples. In contrast, the quantities of these genes in the St. Louis River and Lake Superior were typically below detection. Analysis of sequences of tet(W) gene fragments from four different samples collected throughout the study site supported the conclusion that tertiary-treated municipal wastewater is a point source of resistance genes into Duluth-Superior Harbor. This study demonstrates that the discharge of exceptionally treated municipal wastewater can have a statistically significant effect on the quantities of antibiotic resistance genes in otherwise pristine surface waters.


Asunto(s)
Bacteroides/genética , Agua Dulce/microbiología , Genes Bacterianos , Resistencia a la Tetraciclina , Eliminación de Residuos Líquidos , Heces/microbiología , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos
5.
Health Syst Reform ; 5(1): 66-77, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30924744

RESUMEN

Community engagement describes a complex political process with dynamic negotiation and renegotiation of power and authority between providers and recipients of health care in order to achieve a shared goal of universal health care coverage. Though examples exist of community engagement projects, there is very little guidance on how to implement and embed community engagement as a concerted, integrated, strategic, and sustained component of health systems. Through a series of case studies, this article explores the factors that enable community engagement particularly with a direct impact on health systems.


Asunto(s)
Participación de la Comunidad/métodos , Implementación de Plan de Salud/métodos , Cobertura Universal del Seguro de Salud , Atención a la Salud , Humanos , Política
6.
Chemosphere ; 90(8): 2261-6, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23159070

RESUMEN

Antibiotics and antibacterials are present in water bodies worldwide but little is known about their effects on the biological processes often used to treat water. In this research, the effect of antibiotics on bacterial activity and community structure was investigated by growing biofilms in the presence and absence of a mixture of three compounds (sulfamethoxazole, erythromycin, and ciprofloxacin) in a continuous-flow rotating annular bioreactor fed acetate as a carbon and energy source. Steady-state, surface area-normalized substrate utilization rates for all antibiotic treatments (all at 0.33 µg L(-1), all at 3.33 µg L(-1), and 1 at 3.33 µg L(-1) with the other 2 at 0.33 µg L(-1)) were similar to the control experiments. Higher attached biomass levels in the experiments with ciprofloxacin at 3.33 µg L(-1) resulted in lower steady-state biomass-normalized substrate utilization rates in comparison to other runs. Microbial community analyses via automated ribosomal intergenic spacer analysis revealed significant shifts in community structure for the experiments dosed with the highest concentrations of ciprofloxacin, suggesting that the antibiotic selected for more resistant bacterial strains. The results of this research also suggest that mixtures of antibiotics at the sub-µg L(-1) concentrations typically observed in surface waters are unlikely to affect biological process performance, at least in terms of the degradation of easily assimilable compounds. Conversely, changes to community structure and biofilm quantity might be expected with ciprofloxacin at µg L(-1) concentrations.


Asunto(s)
Acetatos/metabolismo , Antibacterianos/toxicidad , Bacterias/efectos de los fármacos , Biopelículas/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Acetatos/análisis , Biodegradación Ambiental , Reactores Biológicos , Microbiología del Agua , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo
7.
Water Res ; 45(3): 1280-6, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21044793

RESUMEN

The photolysis of two antibacterial compounds, sulfamethoxazole and trimethoprim, was studied in wastewater effluent. The rate of loss of sulfamethoxazole was enhanced in wastewater effluent due to indirect photolysis reactions, specifically reactions with hydroxyl radicals and triplet excited state effluent organic matter. Photolysis in the presence of natural organic matter, however, did not lead to enhanced degradation of sulfamethoxazole. Trimethoprim was also found to be susceptible to indirect photolysis in wastewater effluents, with hydroxyl radical and triplet excited effluent organic matter being the responsible species. Deoxygenation of solutions led to more rapid direct photolysis of sulfamethoxazole and trimethoprim, indicating that direct photolysis proceeds through a triplet excited state, which was verified by demonstrating that trimethoprim is a singlet oxygen sensitizer. In the wastewater effluents tested, photolysis could be apportioned into direct photolysis (48% for sulfamethoxazole, 18% for trimethoprim), reaction with hydroxyl radicals (36% and 62%, respectively) and reaction with triplet excited effluent organic matter (16% and 20%, respectively). These results indicate that allowing photolysis in wastewater stabilization ponds or wastewater treatment wetlands may lead to enhanced pharmaceutical removal prior to discharge and that effluent organic matter has different photoreactivity than natural organic matter.


Asunto(s)
Fotólisis , Sulfametoxazol/química , Trimetoprim/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Oxígeno/química
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