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231.

Food nitrogen (N) and phosphorus (P) footprints are indicators for determining the losses of N and P over food production (FP) and food consumption (FC) chain. Yemen is an interesting case because, given the country’s heavy dependence on food imports, food insecurity, and poverty, the N footprint (NF) and P footprint (PF) could affect its future development. However, NF and PF over time have not yet been studied in Yemen. Therefore, this is the first paper to compute the NF and PF in Arabian Peninsula (a case study from Yemen) by an adjusted model of N-Calculator, by computing virtual N (VNFs) and virtual P (VPFs) factors for main foodstuffs. The NF (kg N cap?1 year?1) and PF (kg P cap?1 year?1) elevated from 5.56 and 1.20 in the 1960s to 15.2 and 4.79 during 2011–2017, respectively, while the national NF (Gg [109 g] N year?1) and national PF (Gg P year?1) increased from 27.7 and 6.77 in the 1960s to 358 and 122 during 2011–2017, respectively. Cereal was the largest contributor to the NF and PF in Yemen over the past 57 years. FP contributes approximately 80% and 86% of the total NF and PF during 2011–2017. Therefore, if possible, the best way for consumers and farmers in Yemen to decrease NF and PF is to focus efforts on increasing FP and FC of foodstuffs with less VNFs and VPFs. The consumption of vegetable-fruit, legumes, starchy, eggs, poultry, and fish should be increased as their NF and PF are low. However, people in Yemen suffer from shortage of resources and lack of awareness, and thus they do not have the opportunity to choose foodstuffs that are low in NF and PF. Accordingly, policymakers should encourage integrated approaches that introduce powerful tools for controlling crop and livestock production in conjunction with enhancements in nutrient use efficiency.

  相似文献   
232.
Environmental Science and Pollution Research - To understand the nexus between economic growth and energy sources, in this study, we have selected Pakistan and collected data over the period...  相似文献   
233.
Environmental Science and Pollution Research - The COVID-19 pandemic needs immediate solution before inflicting more devastation. So far, China has successfully controlled transmission of COVID-19...  相似文献   
234.
Environmental Science and Pollution Research - This research aims to study the safety and efficacy of doravirine in the treatment of HIV-1 (human immunodeficiency virus) patients. We conducted an...  相似文献   
235.
Environmental Science and Pollution Research - The agricultural waste of orange peels (OPs) was utilized as a cheap biosorbent and then tested for its ability to treat the reactive red (RR) dye...  相似文献   
236.
Nanosized Ba1- xBixFe1-xCuxO3(12–50 nm) with x values of 0, 0.01, 0.05, and 0.1 system was prepared using the Pechini method. Structural, morphological, surface and optical characterizations were performed for the prepared samples. Cubic phase was the predominant phase for the undoped BaFeO3 and Bi and Cu co-doped BaFeO3 samples. Minor phases of monoclinic Ba2Fe2O5, orthorhombic BaFe  相似文献   
237.
Nanoscale zerovalent iron/magnetic carbon(NZVI/MC) composites were successfully synthesized by simply calcining yellow pine and iron precursors. NZVI/MC pyrolyzed at 800°C(NZVI/MC800) had a higher percentage of NZVI and displayed better resistance to aggregation and oxidation of NZVI than samples prepared at other temperatures. The NZVI/MC800 material was applied for the elimination of U(Ⅵ) from aqueous solutions. The results suggested that the NZVI/MC800 displayed excellent adsorption capacity(203.94 mg/g)toward U(Ⅵ). The significant adsorption capacity and fast adsorption kinetics were attributed to the presence of well-dispersed NZVI, which could quickly reduce U(Ⅵ) into U(Ⅳ), trapping the guest U(Ⅳ) in the porous biocarbon matrix. The removal of U(Ⅵ) on the NZVI/MC samples was strongly affected by solution pH. The NZVI/MC samples also displayed outstanding reusability for U(Ⅵ) removal after multiple cycles. These findings indicate that NZVI/MC has great potential for remediation of wastewater containing U(Ⅵ).  相似文献   
238.
In recent years, the application of heterogeneous photocatalytic water purification processes has gained wide attention due to its effectiveness in degrading and mineralizing the recalcitrant organic compounds as well as the possibility of utilizing the solar UV and visible-light spectrum. This paper aims to review and summarize the recent works on the titanium dioxide (TiO(2)) photocatalytic oxidation of pesticides and phenolic compounds, predominant in storm and wastewater effluents. The effects of various operating parameters on the photocatalytic degradation of pesticides and phenols are discussed. Results reported here suggest that the photocatalytic degradation of organic compounds depends on the type and composition of the photocatalyst and, light intensity, initial substrate concentration, amount of catalyst, pH of the reaction medium, ionic components in water, solvent types, oxidizing agents/electron acceptors, catalyst application mode, and calcination temperature in the water environment. A substantial amount of research has focused on the enhancement of TiO(2) photocatalysis by modification with metal, non-metal and ion doping. Recent developments in TiO(2) photocatalysis for the degradation of various pesticides and phenols are also highlighted in this review. It is evident from the literature survey that photocatalysis has good potential to remove a variety of organic pollutants. However, there is still a need to determine the practical utility of this technique on a commercial scale.  相似文献   
239.
The epidemiology of tornado-related disasters in the developing world is poorly understood. An August 2005 post-tornado cohort study in rural Bangladesh identified elevated levels of death and injury among the elderly (≥ 60 years of age) (adjusted odds ratio (AOR) = 8.9 (95 per cent confidence interval (CI): 3.9-20.2) and AOR = 1.6 (95 per cent CI: 1.4-1.8), respectively), as compared to 15-24 year-olds, and among those outdoors versus indoors during the tornado (AOR = 10.4 (95 per cent CI: 5.5-19.9) and AOR = 6.6 (95 per cent CI: 5.8-7.5), respectively). Females were 1.24 times (95 per cent CI: 1.15-1.33) more likely to be injured than males. Elevated risk of injury was significantly associated with structural damage to the house and tin construction materials. Seeking treatment was protective against death among the injured, odds ratio = 0.08 (95 per cent CI: 0.03-0.21). Further research is needed to develop injury prevention strategies and to address disparities in risk between age groups and between men and women.  相似文献   
240.
Malaysia has experienced several haze events since the 1980s as a consequence of the transboundary movement of air pollutants emitted from forest fires and open burning activities. Hazy episodes can result from local activities and be categorized as "localized haze". General probability distributions (i.e., gamma and log-normal) were chosen to analyze the PM(10) concentrations data at two different types of locations in Malaysia: industrial (Johor Bahru and Nilai) and residential (Kota Kinabalu and Kuantan). These areas were chosen based on their frequently high PM(10) concentration readings. The best models representing the areas were chosen based on their performance indicator values. The best distributions provided the probability of exceedances and the return period between the actual and predicted concentrations based on the threshold limit given by the Malaysian Ambient Air Quality Guidelines (24-h average of 150 μg/m(3)) for PM(10) concentrations. The short-term prediction for PM(10) exceedances in 14 days was obtained using the autoregressive model.  相似文献   
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