We have previously shown that diarrheagenic Escherichia coli (DEC) and non-DEC are prevalent in food sources and irrigation water in South Africa. Recent data suggest that an increased relative abundance of faecal Enterobacteriaceae is associated with poorer health outcomes among children in developing countries. Thus, exposure to non-DEC from environmental sources may incur adverse effects, although the mechanisms underlying these effects remain obscure. To further elucidate this phenomenon, we assayed non-DEC strains from environmental sources in South Africa for phenotypes that may be associated with intestinal dysfunction (ID). DEC strains were also used. The strains had previously been isolated from Producer Distributor Bulk Milk (PDBM), irrigated lettuce, street vendor coleslaw and irrigation water.In-vitro assays identified; biofilm formation (n = 38), extracellular polymeric substance (EPS) formation (n = 38), cytotoxic activity (n = 10), disruption of tight junctions and induction of Interleukin 8 (IL-8) on polarized T-84 cells (n = 20). The number of strains tested for each assay differed, depending on prior molecular and phenotypic characterization that signalled potential pathogenicity in-vitro. Subsequently, all strains having data points for all analyses were used to compute Principal Component Analysis (PCA) plot curves to infer potential associations amongst test strains and a standard DEC pathogenic strain (042).Biofilm formation on glass coverslips after strains were grown in nutrient-rich media (LB and DMEM-F12 + 0.5% D-Mannose) at 37 °C varied based on pathotype (DEC and non-DEC) and source of isolation (food, irrigation water, clinical) suggesting that pathotype and source isolation influence persistence within a defined environmental niche. Additionally, DEC isolated from irrigated lettuce had a significantly higher (p ≤ 0.05) propensity for biofilm formation in both media compared to all strains including DEC standard controls. This suggested the propensity for irrigated lettuce as a potential source of persistent pathogenic strains. Furthermore, all strains were able to form EPS suggesting the ability to form mature biofilms under conditions relevant for food processing (20–25 °C). Of the (60%, 6 out of 10) strains that showed cytotoxic activity, most (83%, 5 out of 6 strains) were non-DEC isolated from food sources many of which are consumed with minimal processing.Mean percentage reduction in initial TEER (a measure of intestinal disruption), did not significantly differ (p = 0.05) in all test strains from that observed in the standard DEC. Additionally, IL-8 induction from strains isolated from PDBM (139 pg/mL), irrigation water (231.93 pg/mL) and irrigated lettuce (152.98 pg/mL) was significantly higher (p ≤ 0.05) than in the commensal strain aafa. PCA categorized strains based on sources of isolation showed potential for use in source tracking especially when comparing many strains from various environmental sources. We show that non-DEC strains along the food chain possess characteristics that may lead to ID. Further investigations using a larger collection of strains may provide a clearer link to these reported observations that could be associated with the high diarrheal disease burden within the country, especially among infants.

Grazing potential (GP, in % day&minus;1) was estimated for the plankton communities of 13 Greek lakes covering the trophic spectrum, in order to examine its sensitiveness in discriminating different classes of ecological water quality. Lakes with high GP values exhibited high zooplankton biomass dominated by large cladocerans or/and calanoids while lakes with low GP values had increased phytoplankton biomass and/or domination of small-bodied zooplankton indicating intensive fish predation. GP successfully distinguished among ecological water quality classes (estimated using the phytoplankton water quality index PhyCoI) indicating its potential use as a metric for ecological water quality assessment. As a next step, PhyCoI index was modified to include GP as a metric in order to enhance the phytoplankton-based ecological status classification of lakes incorporating zooplankton as a supporting factor. The PhyCoI<inf>GP</inf> successfully assessed the ecological water quality in accordance with PhyCoI classification whereas it was significantly correlated with the eutrophication proxy TSI<inf>SD</inf> based on Secchi Depth. Thus, we propose to use the modified phytoplankton index PhyCoI<inf>GP</inf> for monitoring the ecological water quality of lakes.

Social values structure sustainability practices, including needs-fulfilment practices utilising water–energy–food nexus resources. However, robust theories outlining the interrelations of values, needs and needs-fulfilment practices are lacking. Our aim is to conceptualise and model these interrelations from a sociological perspective that accounts for structure and agency. We do this through a participatory ethnography of a community-based, child-focused food security intervention in rural Eswatini, which defined sustainability in terms of local water–energy–food self-sufficiency. We collected ethnographic data and analysed it informed by a sociological theory of practice, a capabilities-based definition of needs, and a conceptualisation of values as lived and relational. Daily needs-fulfilment practices (lived values) like head-loading and cooking with fuelwood, were influenced by cultural (community-level) values, but primarily structured by (lack of) available resources to enable agents to choose alternative practices. Needs-fulfilment practices held multiple layers of often contradictory meaning. For example, arduous, gendered practices like head-loading water and fuelwood, which detracted from women’s needs like bodily integrity and health, were valued because they were the only actualisable possibilities for fulfilling other needs. Practices that were overtly valued “instrumentally” (materially/economically), were also tacitly valued for fulfilling non-material (socio-cultural) needs, typically associated with “intrinsic” value and altruism. Apparently altruistic practices (i.e., not economically valued) were underpinned by self-interest in social and cultural resource gain. The results highlight important contributions that a (1) philosophically informed, universal definition of needs and (2) sociological conceptualisation that considers structure and agency, can make to further developing plural theories of social values for sustainability.

Grazing potential (GP, in % day^&#8722;1) was estimated for the plankton communities of 13 Greek lakes covering the trophic spectrum, in order to examine its sensitiveness in discriminating different classes of ecological water quality. Lakes with high GP values exhibited high zooplankton biomass dominated by large cladocerans or/and calanoids while lakes with low GP values had increased phytoplankton biomass and/or domination of small-bodied zooplankton indicating intensive fish predation. GP successfully distinguished among ecological water quality classes (estimated using the phytoplankton water quality index PhyCoI) indicating its potential use as a metric for ecological water quality assessment. As a next step, PhyCoI index was modified to include GP as a metric in order to enhance the phytoplankton-based ecological status classification of lakes incorporating zooplankton as a supporting factor. The PhyCoI_GP successfully assessed the ecological water quality in accordance with PhyCoI classification whereas it was significantly correlated with the eutrophication proxy TSI_SD based on Secchi Depth. Thus, we propose to use the modified phytoplankton index PhyCoI_GP for monitoring the ecological water quality of lakes.

We have previously shown that diarrheagenic Escherichia coli (DEC) and non-DEC are prevalent in food sources and irrigation water in South Africa. Recent data suggest that an increased relative abundance of faecal Enterobacteriaceae is associated with poorer health outcomes among children in developing countries. Thus, exposure to non-DEC from environmental sources may incur adverse effects, although the mechanisms underlying these effects remain obscure. To further elucidate this phenomenon, we assayed non-DEC strains from environmental sources in South Africa for phenotypes that may be associated with intestinal dysfunction (ID). DEC strains were also used. The strains had previously been isolated from Producer Distributor Bulk Milk (PDBM), irrigated lettuce, street vendor coleslaw and irrigation water. In-vitro assays identified; biofilm formation (n = 38), extracellular polymeric substance (EPS) formation (n = 38), cytotoxic activity (n = 10), disruption of tight junctions and induction of Interleukin 8 (IL-8) on polarized T-84 cells (n = 20). The number of strains tested for each assay differed, depending on prior molecular and phenotypic characterization that signalled potential pathogenicity in-vitro. Subsequently, all strains having data points for all analyses were used to compute Principal Component Analysis (PCA) plot curves to infer potential associations amongst test strains and a standard DEC pathogenic strain (042). Biofilm formation on glass coverslips after strains were grown in nutrient-rich media (LB and DMEM-F12 + 0.5% D-Mannose) at 37 °C varied based on pathotype (DEC and non-DEC) and source of isolation (food, irrigation water, clinical) suggesting that pathotype and source isolation influence persistence within a defined environmental niche. Additionally, DEC isolated from irrigated lettuce had a significantly higher (p ≤ 0.05) propensity for biofilm formation in both media compared to all strains including DEC standard controls. This suggested the propensity for irrigated lettuce as a potential source of persistent pathogenic strains. Furthermore, all strains were able to form EPS suggesting the ability to form mature biofilms under conditions relevant for food processing (20–25 °C). Of the (60%, 6 out of 10) strains that showed cytotoxic activity, most (83%, 5 out of 6 strains) were non-DEC isolated from food sources many of which are consumed with minimal processing. Mean percentage reduction in initial TEER (a measure of intestinal disruption), did not significantly differ (p = 0.05) in all test strains from that observed in the standard DEC. Additionally, IL-8 induction from strains isolated from PDBM (139 pg/mL), irrigation water (231.93 pg/mL) and irrigated lettuce (152.98 pg/mL) was significantly higher (p ≤ 0.05) than in the commensal strain aafa. PCA categorized strains based on sources of isolation showed potential for use in source tracking especially when comparing many strains from various environmental sources. We show that non-DEC strains along the food chain possess characteristics that may lead to ID. Further investigations using a larger collection of strains may provide a clearer link to these reported observations that could be associated with the high diarrheal disease burden within the country, especially among infants. | The Department of Research and Innovation, University of Pretoria for a post-graduate travel bursary to Matthew Aijuka to travel to James P. Nataro's laboratory at The University of Virginia. Work in the Nataro lab was supported by US National Institutes of Health grant AI-33096 to JPN. | http://www.elsevier.com/locate/foodcont | 2020-08-01 | hj2019 | Food Science

Supply systems for water, energy and food in the Gulf region are becoming highly interlinked. In the last decades, interdependence was evident in the increase of coproduction plants and the cross-sectoral resource use footprints. In light of increasing integration due to growing scarcities, the construction of mega projects for coproduction, and the use of renewables across sectors, the security notion can be revisited. This paper proposes a view of the resource supply security based on the systems' characteristics under change and their ability to deal with risks and shocks (resilience). It introduces internal and external risk factors for the water, energy and food supply systems in the Gulf region and highlights recent knowledge on such risks. Further, the paper explains the vulnerability of supply systems to planning risks like scale, integration intensity and level of service provisions together with risks related to growth, technology, market and climate. In light of such insecurities, we stress the importance of investing in risk management and resilience policies in infrastructure planning. Response measures to future risks can focus on options like storage, knowledge, diversification and, importantly, promoting regional cooperation and synergies from common infrastructure planning between countries of the Gulf Cooperation Council (GCC). | This research was funded by Qatar University, grant number: QUST-CAS-SPR-2017-24. The publication of this article was funded by the Qatar National Library. | Scopus

The provision of reliable water resources, safe grain production, and sustainable energy supply can be deemed as key guarantees for economic growth and human living improvement, but which have been challenged by imbalance relationship between increasing demand and limited supply capacity. In this study, a sustainable water-food-energy plan has been developed to conduct an optimal framework into a multiple water-reservoir system for confronting regional natural and artificial damages such as water deficit, food crisis and electric insufficient contemporarily. A simulation-optimization approach has been proposed to handle multiple uncertainties due to climatic and socioeconomic changes. The proposed approach has advantages of reflecting the climatic change in a lumped and conceptual way; meanwhile, it is effective to deal with socioeconomic uncertainties regarded as probability and possibility distributions, reducing the risk of decision-making with Green criterions. The developed water-food-energy plan with simulation-optimization approach can be applied to a real case study of Jing River, China. The obtained results of water-food-energy shortage, optimal water allocation-food production-energy generation, flood control, and system benefit under various policy-scenarios can be identify comprehensive water-food-energy alternatives in a multi-reservoir optimization system. Meanwhile, the results associated with credibility confidence, risk-averse attitude parameter and robustness coefficient can support the generation of a water-food-energy plan with a robust manner. It can support the improvement of water supply, irrigative production, energy generation, industrial pattern adjustment, flood risk control, supply capacity at a regional view, with aim to achieve sustainability of human activities and resource-energy conservation.

Payment for Ecosystem Services (PES) is not only a prominent, globally promoted policy to foster nature conservation, but also increasingly propagated as an innovative and self-sustaining governance instrument to support poverty alleviation and to guarantee water, food, and energy securities. In this paper, we evaluate a PES scheme from a multi-scalar and political-ecology perspective in order to reveal different power dynamics across the Water-Energy-Food (WEF) Nexus perspective. For this purpose, we analyze the PES scheme implemented in the Hidrosogamoso hydropower project in Colombia. The paper shows that actors&rsquo; strongly divergent economic and political power is determinant in defining how and for whom the Nexus-related water, food, and energy securities are materialized. In this case, the PES scheme and its scalar politics, as fostered by the private/public hydropower alliance, are instrumental to guaranteeing water security for the hydropower scheme, which is a crucial building-block of Colombia&rsquo;s energy security discourse. For this, the water and food securities of the adjacent, less powerful communities are sacrificed. Examining the on-the-ground politics of WEF Nexus is key to understanding their impact on equitable and sustainable governance of water, energy, and food in the everyday lives of millions of resource users. We conclude that politicizing the Nexus can help to trace both the flows of resources and the flows of power.

Supply systems for water, energy and food in the Gulf region are becoming highly interlinked. In the last decades, interdependence was evident in the increase of coproduction plants and the cross-sectoral resource use footprints. In light of increasing integration due to growing scarcities, the construction of mega projects for coproduction, and the use of renewables across sectors, the security notion can be revisited. This paper proposes a view of the resource supply security based on the systems&rsquo; characteristics under change and their ability to deal with risks and shocks (resilience). It introduces internal and external risk factors for the water, energy and food supply systems in the Gulf region and highlights recent knowledge on such risks. Further, the paper explains the vulnerability of supply systems to planning risks like scale, integration intensity and level of service provisions together with risks related to growth, technology, market and climate. In light of such insecurities, we stress the importance of investing in risk management and resilience policies in infrastructure planning. Response measures to future risks can focus on options like storage, knowledge, diversification and, importantly, promoting regional cooperation and synergies from common infrastructure planning between countries of the Gulf Cooperation Council (GCC).