Molecular Detection of human Noroviruses in Influent and Effluent Samples From Two Biological Sewage Treatment Plants in the Region of Monastir,Tunisia

Noroviruses (NoVs) are responsible for numerous cases of waterborne and foodborne gastroenteritis every year. They are released in the sewage and their detection in this environment can reflect the epidemiology of the viral strains circulating in the community. A three-year (2007–2010) survey was conducted in order to evaluate the presence of human NoVs using RT-PCR in 518 sewage samples collected at the entrance and exit of two biological sewage treatment plants located in Monastir region, Tunisia. In this study, we aimed to genetically characterize the most prevalent GI and GII NoV strains, in order to obtain a rough estimate of the efficacy of disinfection treatments and to compare the results with clinical data documented in the same area during the same period. This work confirms the wide circulation and the genetic diversity of NoVs in Tunisia and the widespread distribution of NoV variants in both raw and treated wastewater. Indeed, NoV was detected in 192 (37.1 %) sewage samples, among them mixed infections with group A rotavirus were detected in 125 (65.1 %) cases. The genotypes of the GI NoVs were GI.1, GI.2, GI.4, GI.5, and GI of unassigned genotype (GI.UA), and the genotypes of the GII NoVs were all GII.12. This study enhances the currently poor environmental virological data gathered in Tunisia, demonstrates the benefit of environmental surveillance as a tool to determine the epidemiology of NoVs circulating in a given community, and underlines the need for the design and support of similar long-term studies in our country, in order to compensate for the absence of a national surveillance system for gastroenteric viruses.     

Modification of Thermo-Mechanical Properties of Recycled PET by Vinyl Acetate (VAc) Monomer Grafting Using Gamma Irradiation

Vinyl acetate (VAc) monomer of different percentage was grafted onto the recycled polyethylene terephthalate (r-PET) films using gamma irradiation. The properties of these modified films were characterized by Fourier transform infrared spectroscopy (FTIR), mechanical properties testing (Tensile strength, Elongation at break), dynamic mechanical analysis (DMA) and thermo-gravimetric analysis (TGA). The Tensile Strength (TS) of the modified PET film increased by 132.25?% to the highest value of 50.12 MPa at 15% VAc monomer concentration at 3 kGy gamma dose, while the elongation at break (EB) decreased by 31.83?%. FTIR was used to investigate the molecular interaction of the modified films. TGA revealed that curve of the modified PET film shifted toward higher temperature region by 95?°C, which is very close to that of PET film made from virgin flakes. The results indicate that modified PET films of better mechanical and thermal properties were successfully prepared using VAc monomer grafting by gamma irradiation technique.     

Could curcumin ameliorate titanium dioxide nanoparticles effect on the heart? A histopathological,immunohistochemical, and genotoxic study

Environmental Science and Pollution Research - The evaluation of the toxicological effects of titanium dioxide nanoparticles (TiO2NPs) is increasingly important due to their growing occupational...     

A Socio-Ecological Investigation of Options to Manage Groundwater Degradation in the Western Desert, Egypt

Under increasing water scarcity, collective groundwater management is a global concern. This article presents an interdisciplinary analysis of this challenge drawing on a survey including 50 large and small farms and gardens in a village in an agricultural land reclamation area on the edge of the Western Desert of Egypt. Findings revealed that smallholders rely on a practice of shallow groundwater use, through which drainage water from adjacent irrigation areas is effectively recycled within the surface aquifer. Expanding agroindustrial activities in the surrounding area are socio-economically important, but by mining non-renewable water in the surrounding area, they set in motion a degradation process with social and ecological consequences for all users in the multi-layered aquifer system. Based on the findings of our investigation, we identify opportunities for local authorities to more systematically connect available environmental information sources and common pool resource management precedents, to counterbalance the degradation threat.     

Distribution and ecological risk of organochlorine pesticides and polychlorinated biphenyls in sediments from the Mediterranean coastal environment of Egypt

Organochlorine contamination in the Mediterranean coastal environment of Egypt was assessed based on 26 surface sediments samples collected from several locations on the Egyptian coast, including harbors, coastal lakes, bays, and estuaries. The distribution and potential ecological risk of contaminants is described. Organochlorine compounds (OCs) were widely distributed in the coastal environment of Egypt. Concentrations of PCBs, DDTs, and chloropyrifos ranged from 0.29 to 377 ng g⁻¹ dw, 0.07 to 81.5 ng g⁻¹ dw, and below the detection limit (DL) to 288 ng g⁻¹ dw, respectively. Other organochlorinated pesticides (OCP) studied were 1–2 orders of magnitude lower. OCP and PCBs had higher concentrations at Burullus Lake, Abu Qir Bay, Alexandria Eastern Harbor, and El Max Bay compared to other sites. OCP and PCB contamination is higher in the vicinity of possible input sources such as shipping, industrial activities and urban areas. PCB congener profiles indicated they were derived from more than one commercially available mixture. The ratios of commercial chlordane and heptachlor metabolites indicate historical usage; however, DDT and HCHs inputs at several locations appear to be from recent usage. The concentrations of PCBs and DDTs are similar to those observed in sediments from coastal areas of the Mediterranean Sea. Ecotoxicological risk from DDTs and PCBs is greatest in Abu Qir Bay, Alexandria Harbor, and El-Max Bay.     

Toxicity of Hg, Cu and Zn on early developmental stages of the European clam (Ruditapes decussatus) with potential application in marine water quality assessment

The toxicity of mercury, zinc and copper on sperm viability, fertilisation and embryogenesis of Ruditapes decussatus was examined. Cu did not affect sperm viability at all the concentrations tested. Conversely, the Zn and Hg significantly (P?<?0.01) reduced sperm viability only at the highest concentration (respectively 512 and 256 μg/l). Cu caused a significant decrease (p?<?0.05) of less than 6% in the fertilisation rate at 128 μg/l and Zn of up to 13% at 64 μg/l. Hg significantly (p?<?0.01) inhibited fertilisation at concentrations as low as 32 μg/l. The median effective concentrations (EC50) reducing rates of embryogenesis by 50% were 21.1 μg Hg/l (0.1 μM), 46.3 μg Cu/l (0.72 μM) and 43.4 μg Zn/l. Therefore, Hg is up to seven times more toxic than Cu (on a molar basis). Ecotoxicity of mercury on larvae survival was also assessed in this work. Result showed a significant (p?<?0.05) reduction of survival after exposure to 4 and 12 μg/l of Hg. The fertilisation rate and embryogenesis were the most sensitive endpoints, although the latter is more advisable for routine assessment of seawater quality because of its greater sensibility.     

Lipid peroxidation in the presence of iron oxides

Exposure to iron oxides dusts may lead to lung cancers among exposed population. To evaluate the involvement of iron‐containing particles in lipid peroxidation by production of reactive oxygen species, hematite, magnetite (iron oxides), and crocidolite (asbestos compound) were tested. The peroxidation was followed by the evaluation of some degradation products of lino‐lenic acid. In a buffered medium, magnetite is higher active than hematite. The addition of an iron chelator (EDTA) or of a reducing agent (ascorbate) in this medium enhances the activity of hematite and magnetite, and the combination of both EDTA and ascorbate increases their activity. Crocidolite is the most active whatever the medium. The appearance of the EDTA‐iron‐oxygen complexes related to the reactivity of these oxides is postulated. These results suggest that the oxidizing activity triggered by hematite and magnetite, in a medium containing an iron chelator and a reducing agent, may lead to damages in biological medium.     

Planning for cooler cities: a plan quality evaluation for Urban Heat Island consideration

ABSTRACT

City strategic plans and enabling policies provide a framework for and inform future development across multiple scales. An exemplar city strategic plan will be one based on evidence, enabled by complementary policy outcomes, and built on the knowledge of the existing landscape. This study evaluated the plan quality of eighteen metropolitan strategic plans for city members in the 100 Resilient Cities initiative. A protocol was developed containing thirty-two indicators to assess plans capacity to act as a strategic planning tool to develop, analyse and implement strategies for the Urban Heat Island (UHI) and climate change mitigation and adaptation. The evaluation indicated that strategies addressing the UHI are rarely included in metropolitan plans. Strategic plans showed a lack of evidence-base to inform the potential actions. Urban warming is often linked to extreme weather events anticipated under climate change, not the UHI as a systemic and increasing phenomenon. We recommend that the pathway to addressing UHI mitigation and adaptation may lie in its nexus to aspects of climate change that concurrently can serve to support liveable and resilient cities.