Search Results (8)

This study introduces a novel, non-invasive X-ray absorption analysis (XRA) method to evaluate the photonic absorption process of granular activated carbon (GAC) in hospital water purification systems. By leveraging digital radiographic images, this innovative technique monitors the deterioration and oxidation of the GAC filter, predicts its remaining lifetime, and estimates its water dechlorinating capacity. Analyzing the entire GAC filter and making a reuse possible, the new XRA method provides valuable insights into the filter’s condition, enhancing water purification efficiency and costs without analyzing subsamples. Complementary analytical techniques on subsamples, taken at various depths, did not yield valuable additional information of the GAC filter exhaustion condition, nor additionally make a reuse impossible. Full article

The Oued Zénati, a vital waterway in Algeria, faces severe pollution from urban discharges, hospital wastewater, and agricultural activities, threatening both the ecosystem and public health. This pollution is characterized by high nutrient levels, suspended solids, and fecal contamination indicators, jeopardizing biodiversity and human well-being. To explore natural restoration solutions, this study assessed the purification potential of reeds (Phragmites australis) found in the Oued Zénati riverbed. Water quality was analyzed at three sites: a non-polluted control site (S1), a wastewater discharge area (S2), and a reed-dense area (S3). Results revealed a significant deterioration in water quality at site S2, with high concentrations of nutrients, suspended solids (SS), and fecal contamination indicators. However, a notable improvement in water quality was observed at site S3, downstream of the reed-dense area, with reductions in fecal coliforms (68.5%), fecal streptococci (92.3%), and phosphates (40.3%), and increased levels of dissolved oxygen (DO). These findings suggest that phytoremediation using P. australis could offer a cost-effective, sustainable, and eco-friendly solution for restoring the Oued Zénati. This study recommends establishing phragmifiltration stations, developing artificial wetlands, and enhancing sanitation systems, including hospital wastewater treatment. Public awareness campaigns promoting water and environmental protection are crucial for long-term success. This phytoremediation approach offers economic, ecological, and aesthetic advantages over conventional wastewater treatment techniques. Full article

Bacteriophage therapy is a promising strategy used to treat antimicrobial-resistant or persistent bacterial infections. More recently, the clinical utility of bacteriophages has been rediscovered due to the rise of multi-drug resistance and their potential use in clinical practice as an additional treatment option. In this study, local municipal wastewater facilities, hospital wastewater systems, and freshwater reservoirs were evaluated for the presence of lytic bacteriophages. These phages were isolated using conventional phage isolation techniques: water sample collection and processing, pre-enrichment with the host bacteria, the spot test, and the double-layer method. Plaques were selected according to their morphology and lytic activity on the target bacteria. Clinical isolates and reference strains belonging to the ESKAPE group were the targets during phage isolation. A total of 210 lytic plaque morphotypes with activity against ESKAPE strains were isolated from 22 water samples. Each isolate was qualitatively evaluated for its ability to inhibit the growth of its host strain. Thirty-one translucent plaques with apparent lytic activity were selected for purification. Of these, 87.1% were isolated from wastewater samples, and 12.9% were isolated from flowing freshwater. Specifically, the phages isolated from the freshwater samples targeted Staphylococcus aureus strains, and no phage from Enterococcus faecium strains was isolated. In conclusion, wastewater samples are a suitable source for the isolation of exogenous lytic phages; however, freshwater could be considered an alternative source for the isolation of lytic phages. Full article

Literature reviews have described the applications of silver, copper, and zinc ions and metallic particles of Cu, Ti, and Zn oxides, which have been found to be useful antimicrobial reagents for the biofunctionalization of various materials and their surfaces. For this purpose, compositions of water dispersions containing emulsions of synthetic copolymers based on acrylic and vinyl monomers, polysaccharides (hydroxyethyl cellulose and starch), and various additives with wetting and stabilizing properties were used. Many stable water dispersions of different chemical compositions containing bioactive chemical compounds (copper silicate hydrate, titanium dioxide, and zinc oxide (and other auxiliary substances)) were developed. They were used for the preparation of thin hybrid coatings having good antimicrobial properties against Gram-negative bacteria (Escherichia coli), Gram-positive bacteria (Staphylococcus aureus), and yeast fungus (Candida albicans). Polyester (PES) and polylactide (PLA) nonwovens were modified using the dip-coating method, while PES and cotton fabrics were biofunctionalized by means of dip-coating and coating methods. The antimicrobial (antibacterial and antifungal) properties of the textile materials (nonwovens and fabrics) biofunctionalized with the above-mentioned bioactive agents exhibiting antimicrobial properties (CuSiO₃, TiO₂, ZnO, or ZnO∙SiO₂) were strongly dependent on the agents’ content in the water dispersions. The PES and PLA nonwovens, modified on the surface with water compositions containing copper silicate hydrate, showed good antibacterial properties against the Gram-negative bacteria Escherichia coli, even at a content of 1 wt.% CuSiO₃∙xH₂O, and against the Gram-positive bacteria Staphylococcus aureus, at the content of at least 5 wt.% CuSiO₃∙xH₂O. The bacterial growth reduction factor (R) was greater than 99% for most of the samples tested. Good antifungal properties against the fungus Candida albicans were found for the PES and PLA nonwoven fabrics modified with dispersions containing 5–7 wt.% CuSiO₃∙xH₂O and 4.2–5.0 wt.% TiO₂. The addition of TiO₂ led to a significant improvement in the antifungal properties of the PES and PLA nonwovens modified in this way. For the samples of PES WIFP-270 and FS F-5 nonwovens, modified with water dispersions containing 5.0 wt.% CuSiO₃∙xH₂O and 4.2–5.0 wt.% TiO₂, the growth reduction factor for the fungus Candida albicans (R) reached values in the range of 80.9–98.0%. These new biofunctionalized polymeric nonwoven textile materials can find practical applications in the manufacture of filters for hospital air-conditioning systems and for the automotive industry, as well as in air purification devices. Moreover, similar antimicrobial modification of fabrics with the dip-coating or coating methods can be applied, for example, in the fabrication of fungi- and mold-resistant garden furniture. Full article

Microorganisms forming a biofilm might become multidrug-resistant by information exchange. Multi-resistant, biofilm-producing microorganisms are responsible for a major portion of hospital-acquired infections. Additionally, these microorganisms cause considerable damage in the industrial sector. Here, we screened several nanoparticles of transition metals for their antibacterial properties. The nanoparticles sizes of nickel (<300 nm) and nickel oxide (<50 nm) were analyzed with transmission electron microscopy. We could show that the antibacterial efficacy of nickel and nickel oxide nanoparticles on Pseudomonas aeruginosa isolated from household appliances and Staphylococcus aureus was the highest. Interestingly, only P. aeruginosa was able to survive at high concentrations (up to 50 mM) due to clustering toxic nanoparticles out of the medium by biofilm formation. This clustering served to make the medium nearly free of nanoparticles, allowing the bacteria to continue living without contact to the stressor. We observed these clusters by CLSM, SEM, and light microscopy. Moreover, we calculated the volume of NiO particles in the bacterial biofilms based on an estimated thickness of 5 nm from the TEM images as an average volume of 3.5 × 10⁻⁶ µm³. These results give us a new perspective on bacterial defense mechanisms and might be useful in industries such as water purification. Full article

The use of thermal and non-thermal atmospheric pressure plasma to solve problems related to agriculture and biomedicine is the focus of this paper. Plasma in thermal equilibrium is used where heat is required. In agriculture, it is used to treat soil and land contaminated by the products of biomass, plastics, post-hospital and pharmaceutical waste combustion, and also by ecological phenomena that have recently been observed, such as droughts, floods and storms, leading to environmental pollution. In biomedical applications, thermal plasma is used in so-called indirect living tissue treatment. The sources of thermal plasma are arcs, plasma torches and microwave plasma reactors. In turn, atmospheric pressure cold (non-thermal) plasma is applied in agriculture and biomedicine where heat adversely affects technological processes. The thermodynamic imbalance of cold plasma makes it suitable for organic syntheses due its low power requirements and the possibility of conducting chemical reactions in gas at relatively low and close to ambient temperatures. It is also suitable in the treatment of living tissues and sterilisation of medical instruments made of materials that are non-resistant to high temperatures. Non-thermal and non-equilibrium discharges at atmospheric pressure that include dielectric barrier discharges (DBDs) and atmospheric pressure plasma jets (APPJs), as well as gliding arc (GAD), can be the source of cold plasma. This paper presents an overview of agriculture and soil protection problems and biomedical and health protection problems that can be solved with the aid of plasma produced with electrical discharges. In particular, agricultural processes related to water, sewage purification with ozone and with advanced oxidation processes, as well as those related to contaminated soil treatment and pest control, are presented. Among the biomedical applications of cold plasma, its antibacterial activity, wound healing, cancer treatment and dental problems are briefly discussed. Full article

In recent years, pharmaceutical products have been causing a serious environmental problem in hospital wastewater and water purification plants. The elimination of these pollutants is difficult due to their resistance to biological degradation. Paracetamol has been detected in higher concentrations in hospital wastewater than in other buildings. Activated carbons are a good material for removing paracetamol from hospital wastewater. One of the starting materials to obtain activated carbons is kenaf, which is an easy plant to cultivate. To study the elimination of paracetamol from hospital wastewater by activated carbon, the textural and chemical characterization of activated carbon, as well as the kinetic study and the analysis of the paracetamol adsorption mechanism by the adsorbent, have been carried out. The activated carbon samples studied are micro-mesoporous, with high specific surface values. The chemical composition with presence of oxygen groups favours the adsorption process. The adsorption kinetics were adjusted to a pseudo-second order model. The adsorption mechanism followed the intraparticular diffusion model, carried out in two stages: a fast first stage on the surface of the adsorbent and a slow one inside the pore. Based on the kinetic study, the use of this type of carbon is a good application for the removal of paracetamol from hospital wastewater. Full article

The Friends’ Ambulance Unit (FAU) was created shortly after the outbreak of the First World War. It was an attempt to provide young Friends (Quakers) with the opportunity to serve their country without sacrificing their religious principles. However, it was considered by some members to be in direct opposition to the Society’s fundamental religious tenets, and thus remained a cause of internal conflict throughout the war. Nevertheless, the civilian relief work that was carried out by the FAU early in the war, in the region of Flanders, aligned the unit’s activities much more closely with the religious principles of the Society. The FAU assisted thousands of civilians trapped in the besieged and battered town of Ypres, working intensively in the containment and treatment of the typhoid epidemic that swept the region, locating sufferers, providing them with medical care, and inoculating people against the disease. It helped in the purification of the town’s contaminated drinking water, and distributed milk for infants and food and clothing to the sick and needy. It helped found hospitals and orphanages, made provision for schooling, and organised gainful employment for refugees. Full article