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1.
Environ Monit Assess ; 193(8): 463, 2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-34218333

RESUMO

Sustainable development is a grand challenge of the present century, with tremendous direct and indirect implications for a range of social, economic, and environmental factors. This research proposes a water-centric framework for evaluating "relative" sustainability of the status quo in a country via a new "hydro-social-economic-environmental sustainability index" (HSEESI). We test this framework across 35 countries of American continent using national-scale surveyed data for the 2005-2017 periods. HSEESI possesses four dimensions, namely economic, social development, knowledge and technology, and health sanitation and environment, and 12 related indicators for characterizing these dimensions. Based on the developed HSEESI scores, we assess the linkages between water resources and social-economic-environmental systems at the country level, using single and hybrid-artificial intelligence-gene expression programming (GEP) methods. The former method involves all the indicators, while the latter focuses only on the most effective indicators. Further, we aggregate these analyses at three spatial scales, including American continent, North American countries, and South American countries. Our analyses show that both methods lead to approximate similar results, but the latter is preferred for larger scales as it is more cost effective. Overall, results indicate that the status of water resources in North America is relatively sustainable, whereas in South America, it is relatively unsustainable. Importantly, social development, health sanitation, and environmental dimensions, in both North and South American continents, seem to have a relatively unsustainable status, indicating that water resources systems may not have enough capacity to meet the needs of those dimensions. At the country level, our analyses show that water resources systems of Uruguay, Guyana, and Venezuela may face the highest relative unsustainability, across economic, social development, and health sanitation and environment dimensions. The approach and the framework developed in this study can be applied in other regions around the world and with a more detailed representation of intra-country sustainability issues. It can inform managers and policymakers for sustainable planning and developing water resources projects across scales.


Assuntos
Conservação dos Recursos Naturais , Recursos Hídricos , Inteligência Artificial , Monitoramento Ambiental , América do Sul , Uruguai , Venezuela , Água
2.
Adv Exp Med Biol ; 1328: 199-211, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34981479

RESUMO

BACKGROUND: Acute myocardial infarction (AMI) is a leading cause of death and disability worldwide. Previous investigations have demonstrated that curcumin has a cardioprotective effect and may improve myocardial injury. So this study was performed to assess whether supplementation with curcumin could diminish myocardial injury following AMI. METHODS: To conduct this randomized, double-blinded, and placebo-controlled clinical trial, seventy-two patients with acute myocardial infarction, aged 18-75 years, were enrolled and randomly divided into the active intervention and control groups. The active intervention group (n = 38) received curcumin capsules with piperine supplement (500 mg/day, 95% curcuminoids) for 8 weeks, whereas the control group (n = 34) received a placebo capsule. At the baseline and end of the study, ejection fraction was assessed, and blood samples were taken from all patients to measure the levels of cardiac troponin I(cTnI), lipid profile, FBG, HbA1C, liver enzymes, renal function parameters, and electrolytes. RESULTS: In this trial, curcumin supplementation significantly reduced the levels of HbA1C (-0.3 ± 2.2 vs. +1.1 ± 1.3, P = 0.002), LDL (-10.3 ± 20.7 vs. +0.2 ± 22.5, P = 0.039), ALT (-10.2 ± 28.5 vs. +7.3 ± 39.2, P = 0.029), and ALP (+6.4 ± 39.5 vs. +38.0 ± 69.0, P = 0.018) compared to the placebo group. Moreover, the serum concentration of HDL significantly improved in comparison with the placebo group (+4.5 ± 8.9 vs. -1.6 ± 7.7, P = 0.002). However, no substantial difference was perceived between the groups regarding the ejection fraction and serum levels of cTnI, FBG, renal function parameters, and electrolytes. CONCLUSION: Our results indicated that daily intake of 500 mg of curcumin capsules with piperine supplement for 8 weeks modified lipid profile, liver enzymes, and glycemic status, but did not have any effect on ejection fraction and serum concentration of cardiac troponin I, renal function parameters, and electrolytes in acute myocardial infarction patients.


Assuntos
Curcumina , Infarto do Miocárdio , Alcaloides , Benzodioxóis , Curcumina/uso terapêutico , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Infarto do Miocárdio/tratamento farmacológico , Piperidinas , Alcamidas Poli-Insaturadas
3.
Diabetol Metab Syndr ; 10: 76, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30364300

RESUMO

BACKGROUND: Genome-wide association studies have shown that risk alleles on chromosome 9p21.3 locus, are associated with increasing the risk of cardiovascular diseases (CVDs). Several epidemiological studies have found that metabolic syndrome (MetS) is associated with CVDs. Dietary antioxidants also have shown to have potential favorable effects on MetS prevention. This study examined the interactions between rs1333048 genotypes on 9p21 genetic region and Total antioxidant capacity (TAC) on odds of MetS. METHODS: 263 Tehrani adults were enrolled in this cross-sectional study. The MetS was defined according to the ATPIII. Dietary intake was assessed daily using a FFQ with 147 items. Dietary TAC was assessed according to United States Department of Agriculture database for oxygen radical absorbance capacity (ORAC). Bioelectrical impedance analysis method was used for body analysis and rs1333048 were genotyped by restriction fragment length polymorphism method. Participants were categorized into three groups based on rs1333048 genotypes. RESULTS: The results demonstrate that, prevalence of C allele was 52.85% and A allele was 47.15%. After adjustment for confunder variable, this study demonstrated an interaction between AA genotype and high Lyophilic oxygen radical absorbance capacity (L-ORAC) and high Hydrophilic oxygen radical absorbance capacity (H-ORAC) intake on low odds of MetS (OR = 0.24, 95% CI = 0.06-0.94, P for interaction = 0.04, OR = 0.26, 95% CI = 0.06-0.99, P for interaction = 0.04). Also, our result indicated, there was no interaction between AA genotype and high total oxygen radical absorbance capacity (T-ORAC) and total phenolic intakes on reduce odds of MetS (OR = 0.07, 95% CI = 0.07-1.10, P for interaction = 0.07, OR = 0.58, 95% CI = 0.16-2.07, P for interaction = 0.40) respectively. CONCLUSION: The results of the present study indicate that high L-ORAC and high H-ORAC intake may modify the elevated odds of MetS in AA genotype of rs1333048 on the 9p21 genetic locus.

4.
Water Sci Technol ; 77(7-8): 1838-1850, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29676741

RESUMO

A model was developed for a water resources recovery facility (WRRF) activated sludge process (ASP) in Modified Ludzack-Ettinger (MLE) configuration. Amplification of air requirements and its associated energy consumptions were observed as a result of concurrent circadian variations in ASP influent flow and carbonaceous/nitrogenous constituent concentrations. The indirect carbon emissions associated with the ASP aeration were further amplified due to the simultaneous variations in carbon emissions intensity (kgCO2,eq(kWh)-1) and electricity consumption (kWh). The ratio of peak to minimum increased to 3.4 (for flow), 4.2 (for air flow and energy consumption), and 5.2 (for indirect CO2,eq emission), which is indicative of strong amplification. Similarly, the energy costs for ASP aeration were further increased due to the concurrency of peak energy consumptions and power demands with time of use peak electricity rates. A comparison between the results of the equilibrium model and observed data from the benchmark WRRF demonstrated under- and over-aeration attributed to the circadian variation in air requirements and limitations associated with the aeration system specification and design.


Assuntos
Fontes Geradoras de Energia/estatística & dados numéricos , Gases de Efeito Estufa/análise , Eliminação de Resíduos Líquidos/estatística & dados numéricos , Modelos Teóricos , Esgotos/estatística & dados numéricos , Eliminação de Resíduos Líquidos/instrumentação
5.
Water Res ; 111: 127-139, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28064087

RESUMO

This research systematically studied the behavior of aeration diffuser efficiency over time, and its relation to the energy usage per diffuser. Twelve diffusers were selected for a one year fouling study. Comprehensive aeration efficiency projections were carried out in two WRRFs with different influent rates, and the influence of operating conditions on aeration diffusers' performance was demonstrated. This study showed that the initial energy use, during the first year of operation, of those aeration diffusers located in high rate systems (with solids retention time - SRT-less than 2 days) increased more than 20% in comparison to the conventional systems (2 > SRT). Diffusers operating for three years in conventional systems presented the same fouling characteristics as those deployed in high rate processes for less than 15 months. A new procedure was developed to accurately project energy consumption on aeration diffusers; including the impacts of operation conditions, such SRT and organic loading rate, on specific aeration diffusers materials (i.e. silicone, polyurethane, EPDM, ceramic). Furthermore, it considers the microbial colonization dynamics, which successfully correlated with the increase of energy consumption (r2:0.82 ± 7). The presented energy model projected the energy costs and the potential savings for the diffusers after three years in operation in different operating conditions. Whereas the most efficient diffusers provided potential costs spanning from 4900 USD/Month for a small plant (20 MGD, or 74,500 m3/d) up to 24,500 USD/Month for a large plant (100 MGD, or 375,000 m3/d), other diffusers presenting less efficiency provided spans from 18,000USD/Month for a small plant to 90,000 USD/Month for large plants. The aim of this methodology is to help utilities gain more insight into process mechanisms and design better energy efficiency strategies at existing facilities to reduce energy consumption.


Assuntos
Difusão , Oxigênio , Reatores Biológicos , Cerâmica , Eliminação de Resíduos Líquidos
6.
Environ Sci Technol ; 50(22): 12166-12178, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27804303

RESUMO

The Intergovernmental Panel on Climate Change (IPCC) reported that all carbon dioxide (CO2) emissions generated by water resource recovery facilities (WRRFs) during treatment are modern, based on available literature. Therefore, such emissions were omitted from IPCC's greenhouse gas (GHG) accounting procedures. However, a fraction of wastewater's carbon is fossil in origin. We hypothesized that since the fossil carbon entering municipal WRRFs is mostly from soaps and detergents as dissolved organic matter, its fate can be selectively determined during the universally applied separation treatment processes. Analyzing radiocarbon at different treatment points within municipal WRRFs, we verified that the fossil content could amount to 28% in primary influent and showed varying distribution leaving different unit operations. We recorded the highest proportion of fossil carbon leaving the secondary treatment as off-gas and as solid sludge (averaged 2.08 kg fossil-CO2-emission-potential m-3 wastewater treated). By including fossil CO2, total GHG emission in municipal WRRFs increased 13%, and 23% if an on-site energy recovery system exists although much of the postdigestion fossil carbon remained in biosolids rather than in biogas, offering yet another carbon sequestration opportunity during biosolids handling. In comparison, fossil carbon contribution to GHG emission can span from negligible to substantial in different types of industrial WRRFs. With such a considerable impact, CO2 should be analyzed for each WRRF and not omitted from GHG accounting.


Assuntos
Carbono , Recursos Hídricos , Dióxido de Carbono , Mudança Climática , Fósseis , Efeito Estufa , Esgotos
7.
Sci Total Environ ; 547: 331-344, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26789371

RESUMO

Over the seasonal cycles, the mean cell retention time (MCRT) of the activated sludge process is varied to compensate the wastewater temperature variations. The effects of these variations on the carbon footprint (CFP) and effluent quality index (EQI) of a conventional activated sludge (CAS) process and a nitrification/denitrification (NDN) process were quantified. The carbon emission included both biogenic and non-biogenic carbon. Carbon emissions of wasted biosolids management were also addressed. Our results confirmed that the effluent quality indicated by EQI was not necessarily improved by increasing MCRT. Higher MCRT increased the carbon emission and reduced excess sludge production, which decreased the potential for biogas energy recovery. The NDN process was preferable to the CAS process from the perspective of effluent quality. This consideration extended to the whole plant CFP if the N2O emitted during NDN was limited ([N2O]<1% [NH4(+)]removed) as the carbon emission per unit effluent quality achieved by NDN process is less than that of the CAS process. By putting forward carbon emission intensity (γ) derived from CFP and EQI, our work provides a quantitative tool for decision makers evaluating process alternatives when there is a trade-off between carbon emission and effluent quality.

8.
Sci Total Environ ; 497-498: 711-724, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25087186

RESUMO

A study was conducted to compare the technical potential and effectiveness of different water supply options for securing water availability in a large-scale, interconnected water supply system under historical and climate-change augmented inflow and demand conditions. Part 2 of the study focused on determining the greenhouse gas and renewable energy utilization impacts of different pathways to stabilize major surface reservoir levels. Using a detailed electric grid model and taking into account impacts on the operation of the water supply infrastructure, the greenhouse gas emissions and effect on overall grid renewable penetration level was calculated for each water supply option portfolio that successfully secured water availability from Part 1. The effects on the energy signature of water supply infrastructure were found to be just as important as that of the fundamental processes for each option. Under historical (baseline) conditions, many option portfolios were capable of securing surface reservoir levels with a net neutral or negative effect on emissions and a benefit for renewable energy utilization. Under climate change augmented conditions, however, careful selection of the water supply option portfolio was required to prevent imposing major emissions increases for the system. Overall, this analysis provided quantitative insight into the tradeoffs associated with choosing different pathways for securing California's water supply.

9.
Sci Total Environ ; 497-498: 697-710, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25022721

RESUMO

The technical potential and effectiveness of different water supply options for securing water availability in a large-scale, interconnected water supply system under historical and climate-change augmented inflow and demand conditions were compared. Part 1 of the study focused on determining the scale of the options required to secure water availability and compared the effectiveness of different options. A spatially and temporally resolved model of California's major surface reservoirs was developed, and its sensitivity to urban water conservation, desalination, and water reuse was examined. Potential capacities of the different options were determined. Under historical (baseline) hydrology conditions, many individual options were found to be capable of securing water availability alone. Under climate change augment conditions, a portfolio approach was necessary. The water savings from many individual options other than desalination were insufficient in the latter, however, relying on seawater desalination alone requires extreme capacity installations which have energy, brine disposal, management, and cost implications. The importance of identifying and utilizing points of leverage in the system for choosing where to deploy different options is also demonstrated.

10.
Water Sci Technol ; 68(4): 870-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23985518

RESUMO

The goal of this paper is to show the effect of primary sedimentation on the chemical oxygen demand (COD) and solids fractionation and consequently on the carbonaceous and energy footprints of wastewater treatment processes. Using a simple rational procedure for COD and solids fraction quantification, we quantify the effects of varying fractions on CO2 and CO2-equivalent mass flows, process energy demand and energy recovery. Then we analysed two treatment plants with similar biological nutrient removal processes in two different climatic regions and quantified the net benefit of gravity separation before biological treatment. In the cases analysed, primary settling increases the solid fraction of COD that is processed in anaerobic digestion, with an associated increase in biogas production and energy recovery, and a reduction in overall emissions of CO2 and CO2-equivalent from power importation.


Assuntos
Pegada de Carbono , Precipitação Química , Conservação de Recursos Energéticos/métodos , Eliminação de Resíduos Líquidos/métodos , Carbono/química , Análise de Componente Principal
11.
Water Res ; 45(18): 5858-72, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21943568

RESUMO

Most wastewater treatment plants monitor routinely carbonaceous and nitrogenous load parameters in influent and effluent streams, and often in the intermediate steps. COD fractionation discriminates the selective removal of VSS components in different operations, allowing accurate quantification of the energy requirements and mass flows for secondary treatment, sludge digestion, and sedimentation. We analysed the different effects of COD fractions on carbon and energy footprint in a wastewater treatment plant with activated sludge in nutrient removal mode and anaerobic digestion of the sludge with biogas energy recovery. After presenting a simple rational procedure for COD and solids fractions quantification, we use our carbon and energy footprint models to quantify the effects of varying fractions on carbon equivalent flows, process energy demand and recovery. A full-scale real process was modelled with this procedure and the results are reported in terms of energy and carbon footprint. For a given process, the increase of the ratio sCOD/COD increases the energy demand on the aeration reactors, the associated CO(2) direct emission from respiration, and the indirect emission for power generation. Even though it appears as if enhanced primary sedimentation is a carbon and energy footprint mitigation practice, care must be used since the nutrient removal process downstream may suffer from an excessive bCOD removal and an increased mean cell retention time for nutrient removal may be required.


Assuntos
Pegada de Carbono , Material Particulado/química , Eliminação de Resíduos Líquidos , Purificação da Água/métodos , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Modelos Químicos , Solubilidade , Termodinâmica
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