Qualitative and Quantitative Assessment of Hepatitis A Virus in Wastewaters in Tunisia

Hepatitis A causes substantial morbidity in both industrialized and non-industrialized countries and represents an important health problem in several southern Mediterranean countries. The objectives of the study were as follows: (a) to assess the occurrence of hepatitis A virus (HAV) in Tunisia through the monitoring of urban wastewaters collected at wastewater treatment plants (WTPs); (b) to characterize environmental strains; and (c) to estimate the viral load in raw and treated sewages, in order to evaluate the potential impact on superficial waters receiving discharges. A total of 150 raw and treated wastewaters were collected from three WTPs and analyzed by both qualitative (RT-PCR/nested) and quantitative (qRT-PCR) methods. Of these, 100 (66 %) were found to be positive for HAV by the qualitative assay: 68.3 % in influents and 64.7 % in effluents. The vast majority of HAV sequences belonged to sub-genotype IA, with 11 different strains detected found to be identical to clinical strains isolated from Tunisian patients with acute hepatitis. Five unique variants were also detected, not previously reported in clinical cases. Only two IB strains were found, confirming the rarity of this sub-genotype in this country. The results of the present study indicate a wide circulation of the pathogen in the population, most probably in the form of asymptomatic infections, a finding consistent with the classification of the country as having intermediate/high endemicity. Quantitative data showed high viral loads in influents (3.5E+05 genome copies/liter, mean value) as well as effluents (2.5E+05 genome copies/liter, mean value), suggesting that contaminated water could be a critical element in transmission.     

Revalorization of Macadamia nutshell residue as a filler in eco-friendly castor polyol-based polyurethane foam

Journal of Material Cycles and Waste Management - The use of lignocellulosic fibers as fillers in polymer matrices has aroused the interest of the scientific community and industrial sectors. In...     

Comprehensive investigation of various re-refining technologies of used lubricating oil: a review

Journal of Material Cycles and Waste Management - Waste lubricating oil is considered to be a hazardous waste and has tremendous impact on human health and environment. The present review...     

Production of new concrete with leather tannery waste used as partial replacement of the natural sand

Journal of Material Cycles and Waste Management - Leather production is a technology that boosts the economy because of its versatility and durability. However, the wastes generated throughout the...     

Face mask and medical waste generation in the City of Baguio,Philippines: its current management and GHG footprint

Journal of Material Cycles and Waste Management - The daily use of facemask to prevent virus transmission increases the negative effect on the environment because of improper waste disposal. Due to...     

Changes in the Distribution of Broadleaf Tree Species in the Central Part of the Southern Urals since the 1970s

Russian Journal of Ecology - Changes in the distribution of broadleaf tree species—Tilia cordata Mill., Quercus robur L., Acer platanoides L., and Ulmus glabra Huds.—in the central part...     

Dynamics of Tree and Shrub Vegetation in the Eastern Sayan Mountain Tundra

Russian Journal of Ecology - Climate change entails shifts in the ranges of woody plants along both latitudinal and altitudinal gradients in the boreal forest biome. In this study,...     

Water,sanitation, hygiene and waste disposal practices as COVID-19 response strategy: insights from Bangladesh

Environment, Development and Sustainability - The COVID-19 pandemic has caused a global emergence, and the absence of a proven vaccine or medicine has led to the implementation of measures to...     

Backwater Confluences of the Ohio River: Organic and Inorganic Fingerprints Explain Sediment Dynamics in Wetlands and Marinas

In the Ohio River (OR), backwater confluence sedimentation dynamics are understudied, however, these river features are expected to be influential on the system’s ecological and economic function when integrated along the river’s length. In the following paper, we test the efficacy of organic and inorganic tracers for sediment fingerprinting in backwater confluences; we use fingerprinting results to evidence sediment dynamics controlling deposition patterns in confluences used for wetland and marina functions; and we quantify the spatial extent of tributary drainages with wetland and marina features in OR confluences. Both organic and inorganic tracers statistically differentiate sediment from stream and river end‐members. Carbon and nitrogen stable isotopes produce greater uncertainty in fingerprinting results than inorganic elemental tracers. Uncertainty analysis of the nonconservative tracer term in the organic matter fingerprinting application estimates an apparent enrichment of the carbon stable isotopes during instream residence, and the nonconservativeness is quantified with a statistical approach unique to the fingerprinting literature. Wetland and marina features in OR confluences impact 42% and 11% of tributary drainage areas, respectively. Sediment dynamics show wetland and marina confluences experience deposition from river backwaters with longitudinally linear and nonlinear patterns, respectively, from sediment sources.     

Adaptation of Climate Model Projections of Streamflow to Account for Upstream Anthropogenic Impairments

A statistical procedure is developed to adjust natural streamflows simulated by dynamical models in downstream reaches, to account for anthropogenic impairments to flow that are not considered in the model. The resulting normalized downstream flows are appropriate for use in assessments of future anthropogenically impaired flows in downstream reaches. The normalization is applied to assess the potential effects of climate change on future water availability on the Rio Grande at a gage just above the major storage reservoir on the river. Model‐simulated streamflow values were normalized using a statistical parameterization based on two constants that relate observed and simulated flows over a 50‐year historical baseline period (1964–2013). The first normalization constant is a ratio of the means, and the second constant is the ratio of interannual standard deviations between annual gaged and simulated flows. This procedure forces the gaged and simulated flows to have the same mean and variance over the baseline period. The normalization constants can be kept fixed for future flows, which effectively assumes that upstream water management does not change in the future, or projected management changes can be parameterized by adjusting the constants. At the gage considered in this study, the effect of the normalization is to reduce simulated historical flow values by an average of 72% over an ensemble of simulations, indicative of the large fraction of natural flow diverted from the river upstream from the gage. A weak tendency for declining flow emerges upon averaging over a large ensemble, with tremendous variability among the simulations. By the end of the 21st Century the higher‐emission scenarios show more pronounced declines in streamflow.