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111.
In January 2011, the idea of Millennium Consumption Goals (MCGs) was first proposed at the United Nations, because unsustainable patterns of consumption and production have led to multiple problems threatening the future of humanity. The global economy driven by consumption already uses natural resources equivalent to almost 1.5 planets earth, with the world's richest 1.4 billion consuming almost 85% of global output, which is over 60 fold the consumption of the poorest 1.4 billion. The consumption of the rich is not only ecologically unsustainable, but also “crowding out” the prospects of the poor and exacerbating inequalities that increase the risk of conflict and global unrest. The MCGs provide an innovative future vision and complement the Millennium Development Goals (MDGs) that aim to help the world's poor. First, the MCGs seek to address the issues of global poverty and inequality by ensuring that the basic consumption needs of over 2 billion poor people are met. Next, the MCGs will provide benchmarks for the consumption of the rich, which will reduce the burden on the world's natural resource base. Instead of viewing the affluent as a problem, the novel approach of the MCGs would persuade them to contribute to the solution without having to reduce their quality of life. The MCGs apply even‐handedly to the rich in all countries. The concept enjoys broad support worldwide and is being promoted by a global coalition called the MCG Initiative (MCGI). A bottom‐up approach has already been started by many pioneering individuals, communities, organizations, firms, cities, regions and nations. They prefer not to wait for broad multilateral agreements and are acting now, to voluntarily pursue their own specific MCGs. A parallel top‐down path is being pursued through mandatory agreements at the United Nations/international level, starting with the Rio+20 Earth Summit and beyond. The MCGs fit in with other major UN initiatives like Agenda 21, the MDGs, green economy, SCP and the Sustainable Development Goals.  相似文献   
112.
This investigation was undertaken to determine the effect of culture filtrates of different isolates of Fusarium oxysporum f. sp. lycopersici on mortality of Meloidogyne incognita juveniles and egg hatching. It was observed that different concentrations including standard extract (S.E), 1:10 and 1:100 dilutions of all fungal filtrates inhibited egg hatch when compared with control. Minimum mortality and maximum hatching was observed in BRT (showing least mortality) isolate of F. oxysporum, while maximum mortality and minimum egg hatching was recorded in BGT (showing maximum mortality) isolate. Larval mortality was decreased with a decrease in concentration and the least mortality was observed in 1:100 when compared with SE and 1:10. The potentiality of both the isolates (BRT and BGT) against root-knot nematode M. incognita was confirmed by the pathogenicity test on tomato. These observations confirmed that F. oxysporumisolates possesses variability in pathogenicity ranging from pathogenic to bio-control agent. The plants inoculated with BRT isolate failed to show wilt symptoms while plants inoculated with BGT isolate showed wilt indices.  相似文献   
113.
Severe contamination of water resources including groundwater with iron (Fe) due to various anthropogenic activities has been a major environmental problem in industrial areas of Sri Lanka. Hence, the use of the obnoxious weed, water hyacinth (Eichhornia crassipes (Mart.) Solms) in constructed wetlands (floating aquatic macrophyte-based plant treatment systems) to phytoremediate Fe-rich wastewaters seems to be an appealing option. Although several studies have documented that hyacinths are good metal-accumulating plants none of these studies have documented the ability of this plant grown under different nutrient conditions to remove heavy metals from wastewaters. This paper, therefore, reports the phytoremediation efficiencies of water hyacinth grown under different nutrient conditions for Fe-rich wastewaters in batch-type constructed wetlands. This study was conducted for 15 weeks after 1-week acclimatization by culturing young water hyacinth plants (average height of 20+/-2cm) in 590L capacity fiberglass tanks under different nutrient concentrations of 1-fold [28 and 7.7mg/L of total nitrogen (TN) and total phosphorous (TP), respectively], 2-fold, 1/2-fold, 1/4-fold and 1/8-fold with synthetic wastewaters containing 9.27Femg/L. Another set-up of hyacinths containing only Fe as a heavy metal but without any nutrients (i.e., 0-fold) was also studied. A mass balance was carried out to investigate the phytoremediation efficiencies and to determine the different mechanisms governing Fe removal from the wastewaters. Fe removal was largely due to phytoremediation mainly through the process of rhizofiltration and chemical precipitation of Fe2O3 and FeOH3 followed by flocculation and sedimentation. However, chemical precipitation was more significant especially during the first 3 weeks of the study. Plants grown in the 0-fold set-up showed the highest phytoremediation efficiency of 47% during optimum growth at the 6th week with a highest accumulation of 6707Femg/kg dry weight. Active effluxing of Fe back to the wastewater at intermittent periods and with time was a key mechanism of avoiding Fe phytotoxicity in water hyacinth cultured in all set-ups. Our study elucidated that water hyacinth grown under nutrient-poor conditions are ideal to remove Fe from wastewaters with a hydraulic retention time of approximately 6 weeks.  相似文献   
114.
Environmental Chemistry Letters - The removal of toxic dyes from the wastewater and industrial effluents is a major environmental challenge. Various techniques have been employed for the removal of...  相似文献   
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Municipal solid waste generation in Kathmandu, Nepal   总被引:1,自引:0,他引:1  
Waste stream characteristics must be understood to tackle waste management problems in Kathmandu Metropolitan City (KMC), Nepal. Three-stage stratified cluster sampling was used to evaluate solid waste data collected from 336 households in KMC. This information was combined with data collected regarding waste from restaurants, hotels, schools and streets. The study found that 497.3 g capita(-1) day(-1) of solid waste was generated from households and 48.5, 113.3 and 26.1 kg facility(-1) day(-1) of waste was generated from restaurants, hotels and schools, respectively. Street litter measured 69.3 metric tons day(-1). The average municipal solid waste generation rate was 523.8 metric tons day(-1) or 0.66 kg capita(-1) day(-1) as compared to the 320 metric tons day(-1) reported by the city. The coefficient of correlation between the number of people and the amount of waste produced was 0.94. Key household waste constituents included 71% organic wastes, 12% plastics, 7.5% paper and paper products, 5% dirt and construction debris and 1% hazardous wastes. Although the waste composition varied depending on the source, the composition analysis of waste from restaurants, hotels, schools and streets showed a high percentage of organic wastes. These numbers suggest a greater potential for recovery of organic wastes via composting and there is an opportunity for recycling. Because there is no previous inquiry of this scale in reporting comprehensive municipal solid waste generation in Nepal, this study can be treated as a baseline for other Nepalese municipalities.  相似文献   
119.

Background

Poor knowledge and the lack of deliberation have been cited as reasons for women making uninformed choices about aneuploidy screening. Adequate pre-test counselling is of particular importance where non-invasive prenatal screening (NIPS) is being increasingly offered as a primary screening test.

Design

Women attending the antenatal clinic with a singleton pregnancy below 14 weeks were randomised to receive routine counselling or the intervention—a 16-min educational video on aneuploidy screening before their consult. The primary outcome, rate of informed choice, was assessed using an adapted multidimensional measure of informed choice questionnaire, where informed choice was defined as good knowledge and value-consistent behaviour. Secondary outcomes included informed choice with deliberation, decisional conflict and anxiety.

Results

Two hundred and eighty-six women were recruited. 69.8% of women in the intervention group made an informed choice compared with 53.6% in the control group (Risk Ratio [RR] 1.30, p = 0.014). A significantly higher number of women in the intervention group had good knowledge compared to controls (81% vs. 60.9%; RR 1.33, p = 0.001). Decisional conflict did not differ between groups, but women in the intervention group had higher anxiety scores (p < 0.001).

Conclusion

The study intervention was effective in helping women make informed choice. Qualitative studies to determine the reason for increased anxiety are needed.

Trial registration

Trial registry: ClinicalTrials.gov ; Identifier: NCT05492981.  相似文献   
120.

Wastewater treatment plants (WWTP) are highly non-linear operations concerned with huge disturbances in flow rate and concentration of pollutants with uncertainties in the composition of influent wastewater. In this work, the activated sludge process model with seven reactor configuration in the ASM3bioP framework is used to achieve simultaneous removal of nitrogen and phosphorus. A total of 8 control approaches are designed and implemented in the advanced simulation framework for assessment of the performance. The performance of the WWTP (effluent quality index and global plant performance) and the operational costs are also evaluated to compare the control approaches. Additionally, this paper reports a comparison among proportional integral (PI) control, fuzzy logic control, and model-based predictive control (MPC) configurations framework. The simulation outcomes indicated that all three control approaches were able to enhance the performance of WWTP when compared with open loop operation.

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