Contribution of infection and vaccination to population-level seroprevalence through two COVID waves in Tamil Nadu, India.

This study employs repeated, large panels of serological surveys to document rapid and substantial waning of SARS-CoV-2 antibodies at the population level and to calculate the extent to which infection and vaccination separately contribute to seroprevalence estimates. Four rounds of serological surveys were conducted, spanning two COVID waves (October 2020 and April-May 2021), in Tamil Nadu (population 72 million) state in India. Each round included representative populations in each district of the state, totaling ≥ 20,000 persons per round. State-level seroprevalence was 31.5% in round 1 (October-November 2020), after India's first COVID wave. Seroprevalence fell to 22.9% in round 2 (April 2021), a roughly one-third decline in 6 months, consistent with dramatic waning of SARS-Cov-2 antibodies from natural infection. Seroprevalence rose to 67.1% by round 3 (June-July 2021), with infections from the Delta-variant induced second COVID wave accounting for 74% of the increase. Seroprevalence rose to 93.1% by round 4 (December 2021-January 2022), with vaccinations accounting for 63% of the increase. Antibodies also appear to wane after vaccination. Seroprevalence in urban areas was higher than in rural areas, but the gap shrunk over time (35.7 v. 25.7% in round 1, 89.8% v. 91.4% in round 4) as the epidemic spread even in low-density rural areas

Direct synthesis of nanomaterials on carbon microfibre electrode material for superior electrocatalysis in lake sediment microbial fuel cells

The use of novel and inexpensive catalysts as replacements for platinum is desirable. In this study, we demonstrate for the first time that cost-effective metal oxide nanomaterials and the conductive polymer polyaniline (PANI) can be directly chemically synthesized on carbon microfiber electrodes to improve the performance of lake sediment inoculated MFCs. Nanomaterial of MnO2, MnO2/polyaniline (PANI), ZnO/NiO and ZnO/NiO/PANI attachments were directly chemically synthesized on the carbon material and used as cathode electrodes. The maximum power densities recorded for the different treatments were; MnO2 78.5 mW/m2, MnO2/PANI (Polyaniline) 141.6 mW/m2, ZnO/NiO 67.6 mW/m2, and ZnO/NiO/PANI 129.4 mW/m2. Current and power densities were more than six-fold higher in ZnO/NiO/PANI and MnO2/PANI nanoparticle modified cathodes compared to the control MFCs with no catalyst and more than 2.5 fold higher compared to Pt loaded conventional cathodes. In-excess of 50-fold reductions in catalyst application costs to obtain a unit amount of power was demonstrated with the novel nanomaterials direct deposition method when compared to traditional catalysts such as Pt. This study demonstrates that nanomaterials-incorporated carbon microfiber cathodes bring about significant enhancements to power densities and may potentially have applications in cost-effective MFCs

Contribution of infection and vaccination to seroprevalence through two COVID waves in Tamil Nadu, India

AbstractFour rounds of serological surveys were conducted, spanning two COVID waves (October 2020 and April-May 2021), in Tamil Nadu (population 72 million) state in India. Each round included representative populations in each district of the state, totaling ≥20,000 persons per round. State-level seroprevalence was 31.5% in round 1 (October-November 2020), after India’s first COVID wave. Seroprevalence fell to 22.9% in 2 (April 2021), consistent with waning of antibodies from natural infection. Seroprevalence rose to 67.1% by round 3 (June-July 2021), reflecting infections from the Delta-variant induced second COVID wave. Seroprevalence rose to 93.1% by round 4 (December 2021-January 2022), reflecting higher vaccination rates. Antibodies also appear to wane after vaccination. Seroprevalence in urban areas was higher than in rural areas, but the gap shrunk over time (35.7 v. 25.7% in round 1, 89.8% v. 91.4% in round 4) as the epidemic spread even in low-density rural areas.Article Summary LineAntibodies waned after India’s first COVID wave and both vaccination and infection contributed its roughly 90% seroprevalence after its second wave.</jats:sec

The value of the Modified Early Warning Score and biochemical parameters as predictors of patient outcome in acute medical admissions: a prospective study

Abstract We evaluated the effectiveness of MEWS and biochemical parameters in predicting outcomes for acute medical admissions. Data from consecutive admissions to the Acute Medical Unit (AMU) of National Hospital of Sri Lanka were collected. C-reactive protein (CRP), albumin, white cell count, platelet count and haemoglobin values were collected. Adverse endpoints were HDU/ICU admission, cardio-respiratory emergency/resuscitation and death. A MEWS score of &gt;=5 together with increasing age, pulse rate, respiratory rate, AVPU score, CRP, CRP/Albumin ratio and reduced platelet and albumin level all increased the odds of reaching ‘adverse endpoints”. Adding a score for biochemical parameters increased the area under the ROC curve for reaching “adverse endpoints’. Biochemical parameters better predicted length of hospitalstay and adverse outcomes. A combined scoring system improved the sensitivity of prediction.</jats:p

The Hydrogen Intensity Real-time Analysis eXperiment: Overview and Status Update

The Hydrogen Intensity Real-time Analysis eXperiment (HIRAX) will be a large interferometric array of drift-scan radio telescopes designed to map the large-scale spatial fluctuations of neutral hydrogen in the Universe, in order to better understand the nature of dark energy. It will operate between 400-800 MHz, and is currently under construction in the Karoo desert of South Africa. It will also be a powerful tool for studying astronomical transients and the evolution of galaxies. Here we present an overview of the project, its anticipated deployment timelines, and highlight some of the characterisation and calibration efforts that are currently underway, or planned for the future

Correction: Attrition in serum anti-DENV antibodies correlates with high anti-SARS-CoV-2 IgG levels and low DENV positivity in mosquito vectors-Findings from a state-wide cluster-randomized community-based study in Tamil Nadu, India.

[This corrects the article DOI: 10.1371/journal.pgph.0003608.]