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The development of vaccines and therapeutics that are broadly effective against known and emergent coronaviruses is an urgent priority. We screened the circulating B cell repertoires of COVID-19 survivors and vaccinees to isolate over 9,000 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific monoclonal antibodies (mAbs), providing an expansive view of the SARS-CoV-2-specific Ab repertoire. Among the recovered antibodies was TXG-0078, an N-terminal domain (NTD)-specific neutralizing mAb that recognizes diverse alpha- and beta-coronaviruses. TXG-0078 achieves its exceptional binding breadth while utilizing the same VH1-24 variable gene signature and heavy-chain-dominant binding pattern seen in other NTD-supersite-specific neutralizing Abs with much narrower specificity. We also report CC24.2, a pan-sarbecovirus neutralizing antibody that targets a unique receptor-binding domain (RBD) epitope and shows similar neutralization potency against all tested SARS-CoV-2 variants, including BQ.1.1 and XBB.1.5. A cocktail of TXG-0078 and CC24.2 shows protection in vivo , suggesting their potential use in variant-resistant therapeutic Ab cocktails and as templates for pan-coronavirus vaccine design. [Display omitted] • Next-generation antigen barcoding allows deep mining of antigen-specific antibody repertories • TXG-0078 achieves remarkable breadth by uniquely targeting the SARS-CoV-2 N-terminal domain • A cocktail of complementary coronavirus-specific antibodies shows in vivo protection Broad and potently neutralizing antibodies aid in identifying conserved sites of viral vulnerability; however, such antibodies are often very rare. Hurtado et al. utilize a next-generation antigen barcoding approach to deeply survey the SARS-CoV-2-specific antibody response in COVID-19 survivors and vaccinees, aiming to identify a cocktail of protective antibodies. [ABSTRACT FROM AUTHOR]

The current study involves a simple hydrazine based colorimetric chemo-sensor for selective determination of various anions. The anion-binding ability of the ligand with various anions via polar-non polar interactions and hydrogen bonding has been examined. The sensor displayed significant UV–vis enhancement response to anions such as fluoride, acetate, hydroxide, cyanide and hydrogen sulphate, with respect to concentration and time. The rate constants ( K ) and binding constants, K a , for these anions have been measured by using Benesi-Hildebrand equation. A time dependent NMR study revealed stronger interaction for cyanide and fluoride ions among competing anions. [ABSTRACT FROM AUTHOR]

Abstract: Like many countries, the Central Pollution Control Board (CPCB), Delhi, in India evaluates exceedences of air pollution levels against the National Ambient Air Quality Standards (NAAQS). One of the mandatory requirements for NAAQS compliance is that the probability of non-exceedence should be at least 0.98, meaning that the formulated framework of NAAQS is essentially statistical. The current practice for assessing the compliance criterion is based on simple computation of the count of number of exceedences in a given year, without giving any consideration to the distribution function followed by different pollutants in the ambient air. This becomes even more important for monitoring stations where continuous monitoring is not done for all 365 days, but assessment is based on a minimum sample of 104 readings recorded in a year. The proper method for evaluating the compliance is the foreknowledge of the population distribution and computation of non-exceedence (or exceedence) probability of NAAQS from the probability density function (pdf). The study proposes an integrated and scientifically robust methodology that is generic in nature and could well be used for assessing the air quality compliance criteria laid out by the NAAQS for India, besides suggesting percent reduction in source emissions to those pollutants that exceed the NAAQS. The usefulness of proposed methodology is exhibited by a case study conducted on four criteria air pollutants – sulphur dioxide (SO2), nitrogen dioxide (NO2), suspended particulate matter (SPM), and particulate matter less 10 micron in size (PM10) – monitored in the ambient air of megacity Delhi at six monitoring stations. The collected data at all these sites underwent statistical analysis for the: (i) identification and estimation of the best-fit distributions, (ii) computation of probability of exceedence of the NAAQS for the non-complying pollutants, (iii) determination of return period of NAAQS violation, and (iv) estimation of percentage source emission reduction to meet the NAAQS criteria for the non-complying pollutants using the statistical rollback theory. It was concluded that the knowledge of pdf is a basic and essential requirement for realistically evaluating the compliance of NAAQS. [Copyright &y& Elsevier]

• More than eighty percent adults immune to at least one dengue serotype. • More than half of them are immune to all four dengue serotypes. • Substantial interindividual variation observed in MBC, neutralizing/binding antibodies levels. • Presence of the neutralizing antibodies correlate with presence of binding antibodies, but not vice versa. • Levels of neutralizing and binding antibodies are not in perfect correlation. The Indian population is facing highest dengue burden worldwide supporting an urgent need for vaccines. For vaccine introduction, evaluation and interpretation it is important to gain a critical understanding of immune memory induced by natural exposure. However, immune memory to dengue remains poorly characterized in this region. We enumerated levels of dengue specific memory B cells (MBC), neutralizing (NT) and binding antibodies in healthy adults (n = 70) from New Delhi. NT-antibodies, binding antibodies and MBC were detectable in 86%, 86.56% and 81.63% of the subjects respectively. Among the neutralizing positive subjects, 58%, 27%, 5% and 10% neutralized all four, any three, any two and any one dengue serotypes respectively. The presence of the neutralizing antibodies was associated with the presence of the MBC and binding antibodies. However, a massive interindividual variation was observed in the levels of the neutralizing antibodies (range, <1:50–1:30,264), binding antibodies (range, 1:3,000–1:134,000,) as well as the MBC (range = 0.006%–5.05%). These results indicate that a vast majority of the adults are immune to multiple dengue serotypes and show massive interindividual variation in neutralizing/binding antibodies and MBCs – emphasizing the importance of monitoring multiple parameters of immune memory in order to properly plan, evaluate and interpret dengue vaccines. [ABSTRACT FROM AUTHOR]

Understanding the molecular features of neutralizing epitopes is important for developing vaccines/therapeutics against emerging SARS-CoV-2 variants. We describe three monoclonal antibodies (mAbs) generated from COVID-19 recovered individuals during the first wave of the pandemic in India. These mAbs had publicly shared near germline gene usage and potently neutralized Alpha and Delta, poorly neutralized Beta, and failed to neutralize Omicron BA.1 SARS-CoV-2 variants. Structural analysis of these mAbs in complex with trimeric spike protein showed that all three mAbs bivalently bind spike with two mAbs targeting class 1 and one targeting a class 4 receptor binding domain epitope. The immunogenetic makeup, structure, and function of these mAbs revealed specific molecular interactions associated with the potent multi-variant binding/neutralization efficacy. This knowledge shows how mutational combinations can affect the binding or neutralization of an antibody, which in turn relates to the efficacy of immune responses to emerging SARS-CoV-2 escape variants. [Display omitted] • Identified publicly shared mAbs capable of neutralizing SARS-CoV-2 variants • Defined a new public clonotype containing a CDRH3 CxGGxC motif • Class 1 and 4 RBD antibodies inhibit ACE2 binding through distinct mechanisms • Illustrating RBD mutations accommodation and escape from Omicron Patel et al. describe how a combination of certain mutations affect the binding or neutralization of an antibody and thus have implications for predicting structural features of emerging SARS-CoV-2 escape variants and to develop vaccines or therapeutic antibodies against these. [ABSTRACT FROM AUTHOR]

High surface area Co 3 O 4 /silica-alumina catalyst is reported for selective deoxygenation of biomass derived substrates under moderate conditions. • A straightforward template free preparation of high surface area acidic Co 3 O 4 /Si 2 O 3 Al 2 O 3 is reported. • Prepared catalyst is highly selective towards deoxygenation of palm oil and jatropha oil. • Deoxygenation at 2 bar H 2 pressure provided moderate HDO selectivity with considerable cracking/isomerization. The catalytic deoxygenation of biomass to produce renewable carbon energy addresses major concerns of limited energy sources. In particular, the second-generation biodiesel by selective deoxygenation possesses a higher cetane number, lower cloud point, and higher oxidation stability compared to the fatty acid ester-based biodiesel, and therefore, can be fed directly to the current diesel engines. In present work, we address the significant concerns of cost-effectiveness, high hydrodeoxygenation (HDO) selectivity, modest hydrogen environments, and solvent-free condition using high surface area silica-alumina-supported cobalt oxide nanoparticles as a catalyst to produce fuel-grade hydrocarbons from fatty acid-based feeds that are palm oil and jatropha oil. The catalytic performance is tested for methyl stearate to achieve the best conversion efficiency with remarkable deoxygenation selectivity. The HDO selectivity was as high as 87% at 250 °C and 30 bar H 2 pressure, whereas moderate HDO selectivity with relatively higher cracking was observed at 300 °C and 2 bar H 2 pressure. Remarkably, the HDO selectivity was comparable in the absence of solvent. The catalyst is recyclable with low metal leaching during the deoxygenation. The use of non-noble metal catalysts under solvent-free conditions offers facile production of fuel-grade hydrocarbons. [ABSTRACT FROM AUTHOR]

• The XRD Rietveld analysis reveals a minimal synthesis dependent site inversion. • The Zn 0.4 Co 0.6 Fe 2 O 4 nanoferrite exhibits lowest anisotropy field (HA) of 1.3 kOe. • The spin dynamics study gives lowest spin relaxation time (T 2) for Zn 0.4 Co 0.6 Fe 2 O 4. The present work investigates the static and dynamic magnetization behaviour of Co-Zn nanoferrites and optimizes the magnetocrystalline anisotropy and spin relaxation time. The Co x Zn 1-x Fe 2 O 4 (0 ≤ x ≤ 1) magnetic nanoparticles are synthesized by pH-controlled co-precipitation method. The Le Bail structural refinement of X-ray diffraction patterns confirms the single phase formation with negligible synthesis dependent site inversion. The room temperature static dc magnetization study shows a continuous transition from hard ferrimagnetic CoFe 2 O 4 to soft and weakly magnetic ZnFe 2 O 4 , which has been successfully explained with Yafet-Kittel model. Furthermore, approach-to-saturation analysis gives effective magnetocrystalline anisotropy of 1.45 × 104 J/m3 and lowest anisotropy field of 1.3 kOe for x = 0.4. Next, the dynamic magnetization is studied with Electron Spin Resonance spectroscopy. The lineshape analysis gives highest g-value of 3.88 and lowest spin-relaxation time (T 2) of 4.86 × 10−12 s for x = 0.4, which is in agreement with static magnetization study. The optimized magnetocrystalline anisotropy and lowest spin-relaxation time for Zn 0.4 Co 0.6 Fe 2 O 4 make it a good candidate for use in different biomedical applications. [ABSTRACT FROM AUTHOR]