Antibacterial and Drug Elution Performance of Thermoplastic Blends

Food preservatives or drug compounds can be eluted from polymer substrates to prevent the occurrence of hospital-acquired infections and food spoilage. We investigated the antimicrobial and drug-elution properties of the albumin and zein thermoplastic blends plasticized with glycerol and mixed with varying amounts of low-density polyethylene (LDPE), food preservatives (sodium benzoate or sodium nitrite), and drugs (ampicillin or ciprofloxacin). Bacillus subtilis and Escherichia coli were utilized as Gram (+) and Gram (?) species, respectively, for antimicrobial and drug-elution analyses, since these species are common in the human body and in food environments. The amount of contamination occurring in food and medical applications could be limited with usage of plastic blends made from thermomechanical molding of proteins (albumin from hen egg white and zein from corn), drug eluting compounds, and low-density polyethylene.     

Assessing tungsten transport in the vadose zone: from dissolution studies to soil columns

This study investigates the dissolution, sorption, leachability, and plant uptake of tungsten and alloying metals from canister round munitions in the presence of model, well characterized soils. The source of tungsten was canister round munitions, composed mainly of tungsten (95%) with iron and nickel making up the remaining fraction. Three soils were chosen for the lysimeter studies while four model soils were selected for the adsorption studies. Lysimeter soils were representatives of the typical range of soils across the continental USA; muck-peat, clay-loamy and sandy-quartzose soil. Adsorption equilibrium data on the four model soils were modeled with Langmuir and linear isotherms and the model parameters were obtained. The adsorption affinity of soils for tungsten follows the order: Pahokee peat > kaolinite > montmorillonite > illite. A canister round munition dissolution study was also performed. After 24 d, the measured dissolved concentrations were: 61.97, 3.56, 15.83 mg L⁻¹ for tungsten, iron and nickel, respectively. Lysimeter transport studies show muck peat and sandy quartzose soils having higher tungsten concentration, up to 150 mg kg⁻¹ in the upper layers of the lysimeters and a sharp decline with depth suggesting strong retardation processes along the soil profile. The concentrations of tungsten, iron and nickel in soil lysimeter effluents were very low in terms of posing any environmental concern; although no regulatory limits have been established for tungsten in natural waters. The substantial uptake of tungsten and nickel by ryegrass after 120 d of exposure to soils containing canister round munition suggests the possibility of tungsten and nickel entering the food chain.     

Optimizing process parameters of palm oil bleaching on locally prepared animal bone–based activated carbon using response surface methodology

Adsorptive bleaching potentials of activated animal bone on palm oil was investigated. Palm oil was obtained locally from the mesocarp of oil palm fruits. The obtained palm oil was degummed, neutralized, and subjected to proximate analysis before bleaching. The animal bone–based activated carbon used as a bleaching material was locally prepared by cleaning, drying, carbonization, and chemical activation process. The prepared activated carbon (CBAC) was characterized using Fourier transform infrared, scanning electron microscopy, Braummer–Emmett–Teller, and x‐ray diffraction (XRD) methods. Bleaching of the prepared palm oil on CBAC was done at different process conditions. The characterization results of BET analysis show that CBAC has a surface area of 593.270 m²/g, micropore surface area 595.56 m²/g, micropore volume 0.212 cm³/g, Langmuir surface area 1.38e+04 m²/g, and adsorption energy 3.998 KJ/mol. XRD analysis indicates gypsum as the dominant mineral in the activated carbon sample. The CBAC efficiency of 75.14% was obtained for time/temperature interactions at 50 min/120°C while at 25 g/50 min dosage/time interactions an efficiency of 75.17% was obtained.     

Determinants of CO2 emissions: empirical evidence from Egypt

Environmental and Ecological Statistics - This paper aims to explore the main determinants of environmental quality in Egypt by utilizing the data covering the years from 1971 to 2014. These...     

Accumulation of heavy metals in soil and paddy crop (Oryza sativa), irrigated with water of Ramgarh Lake,Gorakhpur, UP,India

Heavy metals, a highly polluting group of constituents known to exert adverse effects, tend to accumulate in living organisms. The objective of this study was to determine the accumulation and translocation of heavy metals in soil and in paddy crop irrigated with lake water compared to soil and paddy crop irrigated with bore-well water. The quantities of heavy metals (Cd, Cr, Cu, Pb, Zn, As, Mn, and Hg) were determined in different parts of rice plants (Oryza sativa). Results revealed that the mean levels of soil Cd, Cr, Pb, Zn, As, Mn, and Hg in experimental soil and in different parts of rice plant (root, straw, and grain) were higher than the control except for Cu. The content of eight toxic metals was significantly higher in root than in aerial parts of the rice (straw and grains). Rice roots were enriched in Cd, As, Hg, and Pb from the soil, while Cr, Cu, Zn, and Mn were hardly taken by the roots. Bioaccumulation factor for Hg was significantly higher than other heavy metals. Metal transfer factors from soil to rice plants were significant for Cd, Cr, Cu, Pb, Zn, As, Mn, and Hg. The concentrations of metals in lake water were found to be within the permissible limit of Indian standard prescribed by Central Pollution Control Board (2000), except for Hg and As, which were higher than the limit of Indian standard. However, the concentrations of heavy metals in soil and rice grains were still below the maximal levels, as stipulated by Indian Prevention of Food Adulteration Act (PFA, 1954) and World Health Organization (WHO, 1993) guidelines.     

Lipid peroxidation and antioxidant defense enzymes in Clarias gariepinus as useful biomarkers for monitoring exposure to polycyclic aromatic hydrocarbons

The toxicological evaluations of crude oil, xylene, toluene and benzene were carried out against juvenile stages of Clarias gariepinus. On the basis of LC(50) value, benzene (0.017 ml/l) was found to be the most toxic followed by xylene (0.086 ml/l), toluene (0.398 ml/l) and crude oil (2.219 ml/l) was the least toxic. The results of the lipid peroxidation assay showed that the level of malonaldehyde (MDA) in liver and gills of fish exposed to all the test chemicals increased significantly (P < 0.05) when compared to control. Measurement of activities of antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) in liver and gill of fishes exposed to sublethal concentration of the test chemicals over a 28-day period was found to decrease significantly (P < 0.05) when compared to control. The observed reduction in the activities of antioxidant defense enzymes such as SOD, CAT and GST in conjunction with an increase in MDA levels in the gill and liver tissues of test animals exposed to aromatic hydrocarbon compounds were recommended as a good battery of biomarkers for early detection of pollution during biomonitoring programmes.     

Another outlook into energy-growth nexus in Mexico for sustainable development: Accounting for the combined impact of urbanization and trade openness

This study corroborates the importance of United Nations Sustainable Development Goal 7 (SDG-7), intended to ensure access to affordable, reliable, sustainable energy for all, and SDG-8, designed to promote decent work and sustainable economic growth. This article is motivated by the highlighted SDGs and empirically explores the long-run and causality relationship between energy consumption, urbanization, trade openness, and economic growth for annual frequency data from 1965 to 2021 for the case of Mexico. To this end, we leverage the use of fully modified ordinary least squares, dynamic ordinary least squares, and canonical regression estimation methods, while for the direction of causality, the gradual shift and wavelet coherence methods are used. According to the Autoregressive distributed lag (ARDL), the bounds test traces a long-run relationship between the outlined variables over the sampled period. Empirical evidence validates the energy-induced growth hypothesis. This result resonates with the causality analysis, where energy consumption drives economic growth one way in Mexico. This suggests that Mexico cannot embark on energy-conservative policies, as such actions will hurt economic progress. In addition, unidirectional causality is seen between urbanization, trade openness, and economic growth. These findings have far-reaching implications for economic growth and macroeconomic indicators in Mexico. More insights are highlighted in the concluding section.     

Greening the Brazil,Russia, India,China and South Africa (BRICS) economies: Assessing the impact of electricity consumption,natural resources,and renewable energy on environmental footprint

Electricity consumption is a crucial factor in the environmental pollution process, and therefore, its impact needs to be carefully considered by policymakers. This study investigates the relationship between energy consumption, electricity generation, natural resource utilization, and environmental pollution in BRICS nations, which have a substantial share in global resource consumption. To this end, we employed a novel methodology, namely the Method of Moment Quantile Regression (MMQR), for the time period between 1990 and 2018, within the framework of the Environmental Kuznets Curve (EKC) theory. The study's outcome shows that natural resources and renewable energy are efficacious and significant in curbing environmental degradation among the sample countries. The investigation reveals a positive correlation between electricity consumption and environmental degradation, thereby highlighting this vital resource's role in exacerbating the BRICS nations’ ecological footprint. The findings from this research can provide crucial insights for policymakers to achieve sustainable development and carbon neutrality in these countries.