Impact of water matrix on the removal of micropollutants by advanced oxidation technologies

Micropollutants (MPs) in the aquatic compartments are originated from many sources and particularly from the effluents of urban wastewater treatment plants (UWWTPs). Advanced oxidation technologies (AOTs) usually applied after biological processes, have recently emerged as effective tertiary treatments for the removal of MPs, but the oxidation rates of the single compounds may be largely affected by the constituent species of the water matrix. These species include dissolved organic matter and inorganic species (e.g., carbonate, bicarbonate, nitrite, sulphate, chloride). This review analyses the impact of such substances on common AOTs including photolysis, UV/H2O2, Fenton, photocatalysis, and ozone-based processes. The degradation efficiency of single MPs by AOTs results from the combined impact of the water matrix constituents, which can have neutral, inhibiting or promoting effect, depending on the process and the mechanism by which these water components react. Organic species can be either inhibitors (by light attenuation; scavenging effects; or adsorption to catalyst) or promoters (by originating reactive oxygen species (ROS) which enhance indirect photolysis; or by regenerating the catalyst). Inorganic species can also be either inhibitors (by scavenging effects; formation of radicals less active than hydroxyl radicals; iron complexation; adsorption to catalyst or decrease of its effective surface area) or promoters (e.g., nitrate ions by formation of ROS; iron ions as additional source of catalyst). The available data reviewed here is limited and the role and mechanisms of individual water components are still not completely understood. Further studies are needed to elucidate the wide spectrum of reactions occurring in complex wastewaters and to increase the adoption of AOTs in UWWTPs

A case-only study to identify genetic modifiers of breast cancer risk for BRCA1/BRCA2 mutation carriers

Breast cancer (BC) risk for BRCA1 and BRCA2 mutation carriers varies by genetic and familial factors. About 50 common variants have been shown to modify BC risk for mutation carriers. All but three, were identified in general population studies. Other mutation carrier-specific susceptibility variants may exist but studies of mutation carriers have so far been underpowered. We conduct a novel case-only genome-wide association study comparing genotype frequencies between 60,212 general population BC cases and 13,007 cases with BRCA1 or BRCA2 mutations. We identify robust novel associations for 2 variants with BC for BRCA1 and 3 for BRCA2 mutation carriers, P < 10−8, at 5 loci, which are not associated with risk in the general population. They include rs60882887 at 11p11.2 where MADD, SP11 and EIF1, genes previously implicated in BC biology, are predicted as potential targets. These findings will contribute towards customising BC polygenic risk scores for BRCA1 and BRCA2 mutation carriers

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Advances in Carbon Nanostructures

Carbon atoms have the amazing ability to bond in remarkable different manners that can assume distinct astonishing dimensional arrangements from which absolutely diverse and interesting nanostructured carbon materials are obtained. This book aims to cover the most recent advances in (i) Graphene and derivatives, including graphene-based magnetic composites, membranes, wafer devices, and nanofibers for several applications, as well as some particular properties, such as light emission from graphene; (ii) Carbon nanotubes heaters and fibers for reinforcement of cement and diamond-based thin films; and (iii) Nanofluids consisting of both graphene and carbon nanotubes, apart from reporting some important case studies dealing with carbon nanostructures and their use in sensors, coatings, or electromagnetic wave absorbers

Microplastics in the environment: A DPSIR analysis with focus on the responses

This review organizes key information about microplastic pollution through a DPSIR (driving forces, pressures, states, impacts and responses) analysis, namely the current knowledge on the sources of microplastics in the environment, the abundance, mobility and fate of microplastics distributed across the different environmental compartments, as well as their socio-economic and environmental impacts. The available or developing upstream and downstream responses to the microplastic pollution are also reviewed as part of the DPSIR analysis. These include the regulatory and policy instruments, environmental education campaigns, product design, the development of biodegradable plastics, environmental cleanups, waste management, drinking water and wastewater treatment plants, and other treatment technologies and processes. Whenever possible, the current trends and discerning gaps in the research conducted so far by the scientific community are identified, giving some clues to what is going to be the future research on this topic and into new lines of research

Proteobacteria become predominant during regrowth after water disinfection

Disinfection processes aimat reducing the number of viable cells through the generation of damages in different cellular structures and molecules. Since disinfection involves unspecific mechanisms, some microbial populationsmay be selected due to resilience to treatment and/or to high post-treatment fitness. In this study, the bacterial community composition of secondarily treated urban wastewater and of surface water collected in the intake area of a drinking water treatment plant was compared before and 3-days after disinfection with ultraviolet radiation, ozonation or photocatalytic ozonation. The aim was to assess the dynamics of the bacterial communities during regrowth after disinfection. In all the freshly collected samples, Proteobacteria and Bacteroidetes were the predominant phyla (40–50% and 20–30% of the reads, respectively). Surface water differed from wastewater mainly in the relative abundance of Actinobacteria (17% and b5% of the reads, respectively). After 3-days storage at light and room temperature, disinfected samples presented a shift of Gammaproteobacteria (from 8 to 10% to 33–65% of the reads) and Betaproteobacteria (from 14 to 20% to 31–37% of the reads), irrespective of the type of water and disinfection process used. Genera such as Pseudomonas, Acinetobacter or Rheinheimera presented a selective advantage after water disinfection. These variations were not observed in the non-disinfected controls. Given the ubiquity and genome plasticity of these bacteria, the results obtained suggest that disinfection processes may have implications on the microbiological quality of the disinfected water.info:eu-repo/semantics/publishedVersio

Persulfate activation by reduced graphene oxide membranes: Practical and mechanistic insights concerning organic pollutants abatement

The catalytic activity of membranes produced with commercial unmodified reduced graphene oxide (rGO) was demonstrated for the first time in persulfate (PS) activation through experiments performed in continuous mode. Phenol (Ph; C-0 = 5 mg L-1) and venlafaxine (VFX; C-0 = 250 mu g L-1) were employed as model compounds. The influence of the main operation parameters was first investigated considering an operation period of 24 h. For a rGO membrane with an effective area of 2.1 cm(2) , contaminant removal is favored at lower flow rates (0.1 mL min(-1)) and higher catalyst loads (15 mg). Assays carried out under these conditions yielded average removals of 90 and 94% for Ph and VFX, respectively, corresponding to normalized removal rates in the range of 1.71-1.79 L m(-2) h(-1) mg(cat)(-1). Membrane stability tests were conducted in continuous mode for 1 week, allowing to observe a significant catalyst deactivation after 2-3 d of operation, although the catalytic activity could be recovered through simple thermal regeneration procedures. Batch mode oxidation tests employing powder rGO treated at different temperatures (500, 850 and 1000 degrees C) and materials characterization data allowed to conclude that a shift of the surface chemistry character from acidic to basic enhances the catalytic performance. Moreover, scavenging tests indicated that singlet oxygen (O-1(2)), apparently generated by nucleophilic attack of PS to C = O in pyrone-like functionalities, is the main oxidizing species in the rGO-PS system

Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

International audienceBackground: Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods: WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings: Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0–4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2–6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation: In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates. Funding: European Society of Intensive Care Medicine, European Respiratory Society