Due to the implementation of “electrical energy substitution” strategy in China, the proportion of electrical energy in terminal energy consumption is increasing. The improvement of electrical energy efficiency could increase overall energy efficiency. Thus, a special attention should be paid on electrical energy efficiency. An input-oriented epsilon-based measure-DEA (data envelopment analysis) model was used to measure electrical energy efficiency from the perspective of total factor, and the spatial-temporal variability of electrical energy efficiency was investigated. Results draw that the overall electrical energy efficiency is relatively low and shows a downward trend. The eastern region has the best scores of electrical energy efficiency, followed by the central region and then the western region. Furthermore, the main associated determinants were investigated by panel Tobit regression model. It was found that the effect of industrial structure and economic opening degree on electrical energy efficiency is positive on the whole country level, whereas the effect of government intervention and urbanization is negative. From a regional perspective, there are great differences in the effect of each influencing factors. Some corresponding policy recommendations are given.

The development of societies has led information and communication technology (ICT) to play a gradually important role in people’s lives, transforming the way societies and economies function. ICTs are often associated with the path to reducing CO₂ emissions; however, do they lead to that path? Or are they themselves a growing source of energy consumption and emissions? The current study estimates the effect of ICT, trade, economic growth, financial development, and energy consumption on carbon emissions in South and Southeast Asian (SSEA) region for the period of 1990–2014. Moreover, the study also tried to validate the environmental Kuznets curve (EKC) hypothesis between GDP per capita and CO₂ emissions. Cluster analysis was used to identify two groups (potential and advanced countries) based on their social development score. The long-run connection between the variables was examined and the long-run elasticities of ICT, financial development, energy consumption, trade, and economic growth with respect to CO₂ emissions were estimated. Besides, individual country-wise long-run coefficients were found. Results show that financial development and ICT deteriorated the environment quality in the SSEA region, suggesting ICT goods and services are not energy-efficient in both potential and advanced countries and that most of the financial investment was made in non-friendly environmental projects, in potential countries. On the contrary, in advanced countries, financial development mitigates CO₂ emissions. In addition, results also confirmed an inverted U-shaped relationship for all the considered three panels such as potential, advance, and full-countries panels, confirming EKC. Causality findings showed a bidirectional causality between CO₂ emissions and energy consumption as well as unidirectional causality from trade, economic growth, financial development, and ICT to CO₂ emissions. Policymakers should be aware of the ICT impact on energy consumption and strengthen the regulation of their manufacture to facilitate the integration of energy efficiency into user routines. Due to the increasing use of standby mode and Wi-Fi assistive devices, the rapid implementation of legislation regulating these technologies to make them more efficient is recommended.

In the third paragraph of Introduction, the sentence “Few scholars have conducted static studies on dual-wavelength UV photocatalytic technologies (Ma 2018)”.

Shallow lakes are typically either in a clear water state with high abundance of submerged macrophytes or in a turbid state dominated by phytoplankton. A 10-week mesocosm experiment was set up to test the hypothesis that in a very shallow aquatic ecosystem impacted by very high nutrient loading, both submerged macrophytes and phytoplankton may be abundant. Nutrient levels, phytoplankton biomass (measured as chlorophyll a, Chl a), total suspended solids (TSS), inorganic suspended solids (ISS), and submerged macrophyte biomass were measured in three different treatments: DH (deep (1 m) water with very high nutrient loading), SH (very shallow (0.5 m) water with very high nutrient loading), and SL (very shallow (0.5 m) water with low nutrient loading). Of the three treatments, the DH mesocosms exhibited the highest nutrient, the TSS and ISS levels, the highest phytoplankton biomass, and the lowest submerged macrophyte biomass, while the lowest nutrient, the TSS and ISS levels, the lowest phytoplankton biomass, and the highest submerged macrophyte biomass were observed in the SL treatment. All measured parameters exhibited intermediate levels in the SH treatment. Our study demonstrates that in very shallow aquatic ecosystems with very high nutrient loading, submerged macrophytes and phytoplankton may persist in an intermediate but potentially unstable state with medium water clarity. These findings may contribute to the understanding of the mechanisms involved in regime shifts in shallow lakes.

The objective of the present research is to study the levels of reactive oxygen species (ROS) and protein carbonyl (PC) and the functional protein levels of metallothioneins (MT) in Penaeus indicus postlarvae (PL) upon sublethal copper exposure and to determine the biomarkers. The PL were exposed to sublethal copper of 0.164 ppm. The experiments were carried out in the laboratory over a period of 30 days with sampling intervals of 24, 48, and 96 h and 10, 20, and 30 days. The present study confirms that high oxidative stress can be induced from 24 h onwards upon sublethal exposure to copper in P. indicus PL. This is evident from the increasing levels of ROS in the exposed PL during both short-term and long-term exposures to sublethal copper. Since variability in metallothionein levels from 24 h through 30 days of experimental period was observed, metallothioneins cannot be regarded as a good biomarker as far as copper toxicity with respect to P. indicus PL is concerned. The effect of copper on protein carbonyl seems to be very rapid and consistent. The results suggest that protein carbonyl in P. indicus PL is significantly induced in a time-dependent manner upon copper exposure even at sublethal dose, and it seems reasonable to support that protein carbonyl could be used as a biomarker to copper toxicity.

This paper is a maiden empirical attempt to analyze the dynamic causal linkages among urban agglomeration, electricity consumption, construction industry, and economic performance, making use of simultaneous structural equations. A national panel of 30 provinces and three sub-national panels of China, for time span 2000 to 2016, have been estimated employing system and difference generalized method of moments (GMM) estimator. A construction industry-augmented model of economic growth has been proposed, incorporating construction industry and urban agglomeration as exogenous shocks to the aggregate production and electricity consumption as the input of production function. The core empirical results are first, the urban agglomeration and construction industry positively cause electricity consumption but are not caused by the same. It revealed the critical role played by urban agglomeration along with construction industry in boosting electricity consumption. Second, the economic performance positively causes electricity consumption, urban agglomeration, and construction industry and is also caused by the same. Third, urban agglomeration causes the construction industry and is caused by the same. It exposed the mutual role of urban agglomeration and urban industry in reinforcing each other in the times of high economic performance. Finally, among the three regions, the eastern zone is found to be strongest in terms of linkages among urban agglomeration, construction industry, electricity consumption, and economic performance. The intermediate zone is moderately strong, while the western zone is found to have the least strong linkages as compared with the two regions. These results are in line with the sub-national level of economic development of China. These findings, in terms of statistical significance, are highly robust across all the panels. Furthermore, depending upon empirical results, the related strategies are proposed.

In this study, the possibility of culturing Dunaliella salina in stickwater (SW) as the main effluent of fishmeal plants was evaluated. D. salina was grown in different media obtained by replacing standard Guillard medium (F/2) with SW at 0% (control), 10%, 25%, 50%, 75%, and 100% ratios. The cell density, pigment contents, proximate composition, saponification value, and fatty acids (FAs) profiles were measured for 14 days. SW was collected from a kilka fishmeal factory in northern Iran, and the characteristics indicated high concentrations of nitrate (242.00 mg L⁻¹) and phosphate (11.13 mg L⁻¹). A significant increase in the cell density was observed in 14 days when 75% SW was used. Moreover, SW significantly affected the pigment contents. The highest contents of chlorophylls, total carotenoids, and β-carotene (3.64 μg mL⁻¹) were calculated in 75% SW. According to the algal proximate composition, the highest and lowest contents of lipid were accumulated in 75% and 100% SW, respectively (p < 0.05). The highest level of saturated FAs was observed in 75% SW compared with the others (p < 0.05). In conclusion, replacing F/2 with SW indicated the capability of D. salina to grow in a treated medium with 75% SW substitution as a bioremediator.

Statistics from the Intergovernmental Panel on Climate Change (IPCC) reveals that energy consumption remains the main root cause of anthropogenic greenhouse pollutant emissions because of economic expansion. Thus, the need to explore the determinants of environmental degradation in South Africa is pertinent for policymakers and stakeholders. The current study is conducted in a multivariate framework using an augmented carbon income function. The present study explores the theme under review with the inclusion of total natural resource rent as an additional variable to circumvent for omitted variable bias. To this end, annual time series data from 1970 to 2017 is employed for econometrics analysis. The study set off with investigation of stationarity properties with conventional unit root test in conjunction with Zivot-Andrews unit root test that accounts for single structural break. The Pesaran’s bounds testing techniques traces long-run equilibrium relationship between energy (coal) consumption, pollutant emission, total natural resources rent, and economic expansion over the sampled period. Empirical test from the modified Wald test detect and validate feedback causality between energy (coal) consumption and economic expansion. This is instructive to energy stakeholders and policymakers that energy is key determinant of economic growth. Furthermore, total natural resources rent shows significant contribution to pollutant emissions in South Africa. Based on the empirical results, policy direction such as adoption of new technologies and cleaner energy sources were suggested rather than fossil fuel driven economy in South Africa.

Dam construction leads to both sediment discontinuities and the creation of internal phosphorus (P) loads in reservoirs capable of supporting eutrophication. Today, majority of large rivers are dammed and numerous of these infrastructures are constructed in cascade. However, few studies focus on the cumulative effect of the presence of dam on sediment P mobility and bioavailability in downstream reservoirs and rivers parts or throughout the continuum. The influence of three cascade dams has been studied herein on the sedimentary P distribution in surface bed sediments along a 17-km fluvial continuum of the Creuse River (Massif Central, France). The sediments (17 samples) were analyzed for their physical (grain size, specific surface area) and chemical (pH, contents of P, Fe, Al, Ca, Mn, organic matter (OM), and P fractionation) characteristics. Results indicated an amount of P 3 to 7 times higher in dam sediments (1.59 ± 0.51 mgP/g DW) than in free-flowing river sections (0.27 ± 0.11 mgP/g DW). Unexpectedly, sedimentary TP content did not decrease from the first to the third reservoir. The spatial variations of sediment characteristics between river and reservoirs were correlated with the retention of particles sized under 200 μm within the reservoirs. In reservoir sediment, P was mainly associated with the ascorbate fraction (P associated with the redox-sensitive Fe/Mn precipitates). Inside each dam reservoir, longitudinal variations of the sedimentary P distribution were mainly due to the increase of amorphous Fe precipitate content accumulated in fine sediments toward the dam, as characterized by a low Fe-Asc/P-Asc molar ratio. In the river sections, P distribution (mainly associated with HCl and ascorbate fractions) was not significantly influenced by cascade dams.

Non-alcoholic fatty liver disease (NAFLD), the most common form of liver disease, affects over 30% of the US population. Our group and others have previously demonstrated that low-level environmental pollutant exposures were associated with increased odds ratios for unexplained alanine aminotransferase (ALT) elevation, a surrogate biomarker for NAFLD, in the adult National Health and Nutrition Examination Survey (NHANES). However, recently, more sensitive and lower ALT cutoffs have been proposed. The objective of this observational study is to utilize these ALT cutoffs to determine new associations between environmental chemicals and the surrogate NAFLD biomarker. Adult NHANES 2003–2004 participants without viral hepatitis, hemochromatosis, or alcoholic liver disease were analyzed in this cross-sectional study. ALT elevation was defined as > 30 IU/L in men and > 19 IU/L in women. Odds ratios adjusted for potential confounders for ALT elevation were determined across exposure quartiles for 17 pollutant subclasses comprised of 111 individual pollutants. The overall prevalence of ALT elevation was 37.6%. Heavy metal and organochlorine insecticide subclasses were associated with dose-dependent increased adjusted odds ratios for ALT elevation of 1.6 (95% CI 1.2–2.3) and 3.5 (95% CI 2.3–5.5) respectively, for the highest vs. lowest exposure quartiles (pₜᵣₑₙd < 0.01). Within these subclasses, increasing whole blood levels of lead and mercury, and lipid-adjusted serum levels of dieldrin, and the chlordane metabolites, heptachlor epoxide, and trans-nonachlor, were associated with increased odds ratios for ALT elevation. In conclusion, organochlorine insecticide, lead, and mercury exposures were associated with ALT elevation and suspected NAFLD in adult NHANES 2003–2004.