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The Litany River has encountered severe environmental pollution. This study focused on assessing the pollution level in the upper basin of the Litany River by monitoring seasonal variation of water quality and testing physicochemical parameters and microbial qualities. A total of 72 freshwater samples were taken from six sites for 1 year during the four seasons. The microbiological parameters included total coliform, fecal coliform, and Escherichia coli counts. The physicochemical parameters comprised pH, total dissolved solids, nitrate, sodium, potassium, biochemical oxygen demand, chemical oxygen demand, total nitrogen, and total phosphorus. The microbiological quality of samples was evaluated by comparing the fecal pollution indicators loads to the SEQ-EAUX2003 standard for irrigation, and the physicochemical analyses were assessed according to Lebanese Standards Institution (LIBNOR) NL161: 2016 and the World Health Organization (WHO) Guidelines for Water Quality. The results revealed that most physicochemical parameters are not within the permitted limit of LIBNOR and WHO, especially in sites S2, S3, and S6 during the dry seasons. The pH ranged between 6 and 8.16. The total dissolved solids reached 1948 mg/L. The nitrate, sodium, and potassium ranged between 0 and 253 mg/L. The total nitrogen and total phosphorous reached 103 and 5.16 mg/L, respectively. The chemical oxygen demand reached 2210 mg/L, and the biochemical oxygen demand reached 732 mg/L. Concerning the microbiological analysis, fecal pollution was detected in all sites during all seasons, with detectable higher values during the dry seasons, and all samples were considered to be non-conforming, with significant spatiotemporal variation of most parameters. Our results highlight the need to take measures to prevent the high level of pollution. This could be achieved by monthly water quality monitoring of the upper basin and introducing appropriate guidelines to detect pathogens and toxic chemicals that affect the entire ecosystem and lead to severe public health issues.

Relating the ground motion intensity measure (IM) and the structural engineering demand parameter is a crucial step in the performance-based earthquake engineering framework. This study investigates the selection of IM for development of probabilistic seismic demand model of urban shield tunnels subjected to earthquake ground motions in liquefiable and non-liquefiable soils. Nonlinear dynamic effective stress analyses are conducted to develop a database of the intensity measures and structural seismic responses exposed to ground shaking and soil liquefaction. Two advanced soil constitutive models (i.e., Pressure DependMultiYield03 and PressureIndependMultiYield for liquefiable and non-liquefiable soils, respectively) are employed to capture the nonlinear behavior. A suite of 23 ground motion intensity measures is selected and assessed based on the evaluation criteria of correlation, efficiency, practicality and proficiency. Eventually, the multi-level fuzzy comprehensive evaluation method is employed to comprehensively consider the four evaluation criteria and establish the optimal ground motion IM suitable for probabilistic seismic demand analysis of shield tunnel structures. The obtained results show that the sustained maximum acceleration is the optimal IM for evaluating the structural seismic response, followed by the peak ground acceleration in both liquefiable and non-liquefiable soils. Peak pseudo velocity spectrum, displacement square integral and Housner spectral intensity are found to be not suitable for the probabilistic seismic demand analysis of shield tunnel structures.

Increasing income brings about a decline in the relative importance of food consumption, a wider spread of spending patterns, and a demand for higher-quality goods. Using an index-number approach, this article analyzes these three closely-related tendencies. Stripping out the impact of prices from the dispersion of food expenditures gives a volume-based measure of diet diversity that is relevant for nutrition. Using unpublished data from the World Bank's International Comparison Program for 31 items of food in more than 150 countries, we find that diets of rich countries are substantially more diverse than those of the poor; and that volumes are the more appropriate way to measure the inequality of diversity. The quality of the food basket, based on the luxury-necessity distinction of consumption, increases with income, but the elasticity is small. There is a modest tendency for the structure of prices to be regressive since prices of luxuries relative to necessities are lower in richer countries. Additionally, our diversity and quality measures are shown to have implications for demand analysis and well-being.

A test system that combines reality and simulation is an urgent requirement for the combat-oriented demonstration and verification of maritime unmanned equipment in complex scenarios. By analyzing the actual demand and outstanding issues related to maritime unmanned equipment testing, and combining this with the characteristics of maritime unmanned equipment testing tasks at the present stage, a framework for a maritime unmanned equipment testing system based on live virtual constructive (LVC) simulation technology has been designed. This system composition has been proposed, and a typical application has been validated. These ideas provide a foundation for the combat-oriented testing of maritime unmanned equipment.

An Exact Affine Stone Index demand model is estimated to analyze the household-level demand for nine nut products (peanuts, pecans, almonds, cashews, walnuts, pistachios, mixed nuts, macadamia nuts, and other nuts) in the United States using Nielsen Homescan panel data from 2009 through 2015. The demands for all nuts are elastic. All nut products are necessities and substitutes for each other. Household sociodemographic characteristics are statistically significant drivers of the demand for nut products. Finally, the effects of changes in the magnitude of selected promotion expenditure elasticities for nuts are simulated to determine their impacts on prices and quantities demanded.

Supply–demand analysis is an important part of the planning of urban emergency shelters. Using Pudong New Area, Shanghai, China as an example, this study estimated daytime and nighttime population of the study area based on fine-scale land use data, census data, statistical yearbook information, and Tencent user-density big data. An exponential function-based, probability density estimation method was used to analyze the spatial supply of and demand for shelters under an earthquake scenario. The results show that even if all potential available shelters are considered, they still cannot satisfy the demand of the existing population for evacuation and sheltering, especially in the northern region of Pudong, under both the daytime and the nighttime scenarios. The proposed method can reveal the spatiotemporal imbalance between shelter supply and demand. We also conducted a preliminary location selection analysis of shelters based on the supply–demand analysis results. The location selection results demonstrate the advantage of the proposed method. It can be applied to identify the areas where the supply of shelters is seriously inadequate, and provide effective decision support for the planning of urban emergency shelters.

Norfloxacin is often found in wastewater treatment plants, groundwater, and even drinking water causing environmental concerns because of its potential undesirable effects on human health or aquatic ecosystems. However, conventional treatments cannot deal with norfloxacin efficiently. This work proposes an efficiently enzymatic degradation of norfloxacin by chloroperoxidase (CPO). 82.18% degradation efficiency of norfloxacin was achieved after 25 min reaction time at pH 5.0 with an enzyme concentration of 1.5 × 10 −9  mol L −1 . HPLC–MS was used to determine the intermediates or final products. The product analysis and determination of the chemical oxygen demand indicated if the enzymatic degradation by CPO was carried out before the usually existing bioremediation techniques (usually activated sludge) in sewage treatment plant, the effluent containing norfloxacin can be decontaminated more efficiently and thoroughly than that only by activated sludge treatment. The eco-toxicity tests using a green algae, Chlorella pyrenoidosa , indicated that the toxicity of degraded products of norfloxacin was lower than the parent norfloxacin molecule. CPO-catalyzed degradation of norfloxacin is a promising alternative for treating effluent containing norfloxacin. Graphical abstract

We empirically examine the redistributive effects of higher minimum quality standards on consumer welfare. More specifically, we study the impact of the European Union's ban on battery eggs, the previous minimum quality standard, on household egg purchases and evaluate its redistributive effect on consumer welfare. This paper estimates an individual-level demand model for eggs differentiated by animal welfare. Typically, after minimum quality standards for eggs are raised, the price of higher-quality eggs falls. As a result, consumer welfare is redistributed from households that do not value animal welfare to households that are willing to pay a premium for animal welfare. In our analysis of German household data, we find that, on average, households with higher income are willing to pay more for eggs that provide higher animal welfare. This provides evidence that higher minimum quality standards have a regressive impact. In counterfactual scenarios, we estimate the cost reduction that would be needed to offset the regressive effect and find that as retailers’ pricing power increases, the cost reduction must be higher. Finally, we consider hypothetical future scenarios that continue to increase the minimum quality standard until only the highest-quality eggs remain on the market.

This paper presents the probabilistic seismic demand and fragility analyses of a novel mid-rise large-span cassette structure. A newly designed nine-storey office building in Hunan, China, is selected, and its two different design schemes, namely, a traditional frame structure and a novel cassette structure, are examined using numerical models established on the basis of a shake table test. Based on probabilistic seismic theory, the appropriate intensity measures are firstly studied based on a set of 110 seismic records; and PGV and GeoSaavg, which consider the 3D characteristics of the structure, are selected. In addition, the uncertainty of earthquakes, including spectral characteristics, fault distance and input direction, are considered, and 25 seismic records recommended by the Federal Emergency Management Agency are selected. An incident angle interval of 22.5° is selected to consider the uncertainty in the input directions of real earthquakes. Incremental dynamic analyses are conducted, and the structural responses in every individual input direction as well as in all the directions are studied. Finally, probabilistic seismic fragility analysis is conducted, and the probabilities of exceeding different limit states of the frame and cassette structures is presented. Amongst the studies, the novel cassette design can not only achieve much larger span, but also shows a better, more stable seismic performance. Therefore, the cassette structure may be a better alternative in seismic design.

Microbial fuel cells (MFCs) are devices that exploit microorganisms as biocatalysts to degrade organic matter or sludge present in wastewater (WW), and thereby generate electricity. We developed a simple, low-cost single-chamber microbial fuel cell (SCMFC)-type biochemical oxygen demand (BOD) sensor using carbon felt (anode) and activated sludge, and demonstrated its feasibility in the construction of a real-time BOD measurement system. Further, the effects of anodic pH and organic concentration on SCMFC performance were examined, and the correlation between BOD concentration and its response time was analyzed. Our results demonstrated that the SCMFC exhibited a stable voltage after 132 min following the addition of synthetic WW (BOD concentration: 200 mg/L). Notably, the response signal increased with an increase in BOD concentration (range: 5–200 mg/L) and was found to be directly proportional to the substrate concentration. However, at higher BOD concentrations (>120 mg/L) the response signal remained unaltered. Furthermore, we optimized the SCMFC using synthetic WW, and tested it with real WW. Upon feeding real WW, the BOD values exhibited a standard deviation from 2.08 to 8.3% when compared to the standard BOD5 method, thus demonstrating the practical applicability of the developed system to real treatment effluents.