Biochar integrated reactive filtration of wastewater for P removal and recovery, micropollutant catalytic oxidation, and negative CO2 e: Process operation and mechanism.

Biochar (BC) use in water treatment is a promising approach that can simultaneously help address societal needs of clean water, food security, and climate change mitigation. However, novel BC water treatment technology approaches require operational testing in field pilot-scale scenarios to advance their technology readiness assessment. Therefore, the objective of this study is to evaluate the system performance of BC integrated into hydrous ferric oxide reactive filtration (Fe-BC-RF) with and without catalytic ozonation (CatOx) process in laboratory and field pilot-scale scenarios. For this investigation, Fe-BC-RF and Fe-CatOx-BC-RF pilot-scale trials were conducted on synthetic lake water variants and at three municipal water resource recovery facilities (WRRFs) at process flows of 0.05 and 0.6 L/s, respectively. Three native and two iron-modified BCs were used in these studies. The commercially available reactive filtration process (Fe-RF without BC) had 96%-98% total phosphorus (TP) removal from 0.075- and 0.22-mg/L TP, as orthophosphate process influent in these trials. With BC integration, phosphorus removal yielded 94%-98% with the same process-influent conditions. In WRRF field pilot-scale studies, the Fe-CatOx-BC-RF process removed 84%-99% of influent total phosphorus concentrations that varied from 0.12 to 8.1 mg/L. Nutrient analysis on BC showed that the recovered BC used in the pilot-scale studies had an increase in TP from its native concentration, with the Fe-amended BC showing better P recovery at 110% than its unmodified state, which was 16%. Lastly, the field WRRF Fe-CatOx-BC-RF process studies showed successful destructive removals at >90% for more than 20 detected micropollutants, thus addressing a critical human health and environmental water quality concern. The research demonstrated that integration of BC into Fe-CatOx-RF for micropollutant removal, disinfection, and nutrient recovery is an encouraging tertiary water treatment technology that can address sustainable phosphorus recycling needs and the potential for carbon-negative operation. PRACTITIONER POINTS: A pilot-scale hydrous ferric oxide reactive sand filtration process integrating biochar injection typically yields >90% total phosphorus removal to ultralow levels. Biochar, modified with iron, recovers phosphorus from wastewater, creating a P/N nutrient upcycled soil amendment. Addition of ozone to the process stream enables biochar-iron-ozone catalytic oxidation demonstrating typically excellent (>90%) micropollutant destructive removals for the compounds tested. A companion paper to this work explores life cycle assessment (LCA) and techno-economic analysis (TEA) to explore biochar water treatment integrated reactive filtration impacts, costs, and readiness. Biochar use can aid in long-term carbon sequestration by reducing the carbon footprint of advanced water treatment in a dose-dependent manner, including enabling an overall carbon-negative process.

Prevalence and impact of SARS-CoV-2 infection on maternal and infant health in African populations: protocol of a multicentre prospective cohort study (MA-CoV project).

INTRODUCTION: Pregnant women are currently considered a vulnerable population to SARS-CoV-2 infection, with increased risk of severe COVID-19, preterm birth and maternal mortality. There is, however, a paucity of data on the burden of maternal SARS-CoV-2 infection in sub-Saharan countries. The objective of this study is to determine the prevalence and health effects of maternal SARS-CoV-2 infection in selected sites from Gabon and Mozambique. METHODS AND ANALYSIS: MA-CoV (MAternal CoVid) is an observational, multicentre prospective cohort study where 1000 pregnant women (500 per country) will be enrolled at the antenatal clinic visits. Participants will undergo monthly follow-up at each antenatal care visit, delivery and postpartum visit. The primary study outcome is the prevalence of SARS-CoV-2 infection during pregnancy. The clinical presentation of COVID-19 in pregnancy will also be characterised, and incidence of infection during pregnancy will be evaluated, as well as the risk factors of maternal and neonatal morbidity and mortality associated with SARS-CoV-2 infection and the risk of mother to child transmission of SARS-CoV-2. SARS-CoV-2 infection screening will be performed through PCR diagnosis. ETHICS AND DISSEMINATION: The protocol was reviewed and approved by the Comité National d'Éthique pour la Recherche au Gabon, Comité Nacional de Bioética para Saúde de Moçambique and the Ethics Committee of the Hospital Clinic of Barcelona (Spain). Project results will be presented to all stakeholders and published in open access journals. TRIAL REGISTRATION NUMBER: NCT05303168.

The severity of trauma determines the immune response to PF4/heparin and the frequency of heparin-induced thrombocytopenia.

Heparin can induce heparin-induced thrombocytopenia (HIT). The combined effect of type of surgery (major vs minor) and heparin on this prothrombotic immune reaction to platelet factor 4 (PF4)/heparin was analyzed. In a randomized, double-blind study, trauma patients receiving low-molecular-weight (LMWH) or unfractionated heparin (UFH) for thrombosis prophylaxis were assessed for PF4/heparin-antibody seroconversion, HIT, and thrombosis according to type of surgery. The risk for seroconversion was higher than major versus minor surgery odds ratio, 7.98 [95% confidence interval, 2.06-31.00], P = .003, controlled for potential confounders, as was the risk for HIT (2.2% [95% confidence interval, 0.3%-4.1%] vs 0.0%, P = .010). During LMWH compared with UFH thromboprophylaxis, HIT (1 of 298 vs 4 of 316; P = .370) and PF4/heparin seroconversion (1.7% vs 6.6%; P = .002) were less frequent, driven by differences in patients undergoing major surgery (incidence of HIT: LMWH 0.8% vs UFH 4.0%; P = .180; seroconversion rates: 4.0% vs 17.0%; P = .001). After minor surgery, no case of HIT occurred. The severity of trauma and the need for major surgery strongly influence the risk of an anti-PF4/heparin immune response, which is then increased by UFH. In major trauma certoparin may be safer than UFH because it induces HIT-antibody seroconversion, and the corresponding risk of HIT, less frequently.