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Green hydrogen from wastewater─a dual crisis resolution
No full textWith continuous depletion of fossil fuels, a hike in global temperature due to CO2 emissions, and increasing population of Earth, the demand for alternative green renewable energy sources has become undeniable. Hydrogen, a potential fuel for energy production, can be produced in a green way by water electrolysis with little to no carbon emissions. As some parts of the world still face the challenge of a drinking water crisis, using clean, drinkable water for hydrogen production becomes a concern. Households, agriculture, pharmacies, and industries release a lot of polluted wastewater into the environment, increasing biological oxygen demand and causing ecological imbalance. If wastewater is used as a feedstock for producing hydrogen, it can address both the energy crisis and water scarcity. In this review, hydrogen production from wastewater is classified into two parts: direct production and wastewater treatment methods followed by hydrogen generation. The technology, beyond all doubt, can be beneficial for green hydrogen generation, reducing carbon emission and contributing to a net-zero future
A comprehensive overview of the catalytic pathway for CO<sub>2</sub> utilization with epoxide to cyclic carbonate
No full textThis review is focused on the promising area of CO2 utilization with epoxide for cyclic carbonate production through various catalytic pathways of the cycloaddition reaction. Herein, we have attempted to summarize the salient points of the latest research studies on the cycloaddition of CO2 to epoxides and to document the advancements of the relevant catalysts that can convert CO2 to cyclic carbonates under various conditions. It starts with an introduction about the emission sources of CO2 from different sectors and their impact on the environment and CO2 utilization in cyclic carbonates through several epoxides. Recent advances in mechanistic insights and designs of suitable catalysts for cyclic carbonate synthesis are comprehensively discussed in subsequent sections. The catalytic systems have been organized in families of compounds and thoroughly examined in terms of availability, catalytic performance, and mechanistic route. Ultimately, the techno-economic evaluation and various related process designs and simulations are highlighted here
Ionospheric response to PPEF events in the Indian region during high and low intense geomagnetic storms
No full textSpace weather variations can significantly affect ionospheric electron density, which can, in turn, adversely affect various navigational and communication technologies. One such phenomenon is the prompt penetration electric field. The convective electric field from a magnetospheric origin penetrates the lower ionosphere during a geomagnetic storm. The electric field penetrating the ionosphere can challenge space-based technologies. Thus, understanding the convectional electric field from higher latitudes to the low-latitudinal region during geomagnetic disturbance is critical. The ionosphere over the Indian region consists of equatorial and low latitude dynamics, such as equatorial ionization anomaly, that are highly dynamic even during the quiet days. Therefore, understanding the effects of prompt penetration electric field observed in the Equatorial Electrojet is of utmost importance over the Indian region. In the current study, two geomagnetic storms, the St. Patrick's Day storm of 17th March 2015 and another low intense storm of 8th June 2014, were chosen to understand the effects of PPEF over equatorial ionization anomaly. The ionospheric density was enhanced during the relatively less intense geomagnetic storm compared to the St. Patrick's Day storm. In these two events, large-scale ionospheric irregularities were observed from ROTI values during the local daytime hours, but no ionospheric scintillation was detected (S4 index)
Investigating forced transient chaos in monsoon using Echo State Networks
No full textForecasting Indian Summer Monsoon Rainfall (ISMR) is a formidable task due to its intricate variability. This study harnesses the power of machine learning (ML) to decipher the chaotic trajectory within ISMR, drawing inspiration from ML's success in predicting analogous systems. By utilizing ERA-interim data, the method dissects ISMR's chaotic nature through correlation dimension-based techniques. Employing the Lorenz-96 model on daily rainfall data, trained with an Echo State Network (ESN), the technique discerns patterns within a span of 1 model time slightly trailing its performance in other systems. This discrepancy could stem from the intricacies of observational data and the training process involving 500 initial conditions. Notably, this method achieves accuracy in slightly over 50% of cases. Despite its current limitations, this approach exhibits promise in shedding light on the chaotic behaviour enforced in ISMR. As a result, it contributes to the advancement of monsoon forecasting techniqu
Recent Indian contribution in the realms of polar studies
No full textIndian work in Antarctica has covered mainly atmosphere, biology and geoscience domains of sciences in central Dronning Maud land and Princess Elizabeth land (PEL) of eastern Antarctica. While observations of synoptic weather, geophysical and glaciological parameters have continued in both the sectors, thematic earth science studies focusing on crustal evolution and Gondwana fit have gained attention in the PEL where Neoproterozoic as well as Pan-African tectonic and metamorphic events that have established granulite grade metamorphism with peak conditions of ∼ 900 °C and 11 kbar followed by two stages of decompression. In the mafic granulites. The earth’s declining magnetic field and space weather studies have dominated the geophysical investigations. Ice sheet dynamics and deglaciation history have for the first time indicated that the Antarctic ice shelf too are losing ice and shrinking. The recent results of the Southern Ocean expeditions have revealed that the AABW have become fresher (∼ 0.002), warmer (0.04 °C), and sub ducted by ∼ 50–20 m toward the end of the past decade in the Indian Sector of Southern Ocean. Studies in the Arctic have mostly been conducted in the atmosphere and biological fields
Trade-off between the antiviral and vaccinal effects of antibody therapy in the humoral response to HIV
No full textAntibody therapy for HIV-1 infection exerts two broad effects: a drug-like, antiviral effect, which rapidly lowers the viral load, and a vaccinal effect, which may control the viral load long-term by improving the immune response. Here, we elucidate a trade-off between these two effects as they pertain to the humoral response, which may compromise antibody therapy aimed at eliciting long-term HIV-1 remission. We developed a multi-scale computational model that combined within-host viral dynamics and stochastic simulations of the germinal centre (GC) reaction, enabling simultaneous quantification of the antiviral and vaccinal effects of antibody therapy. The model predicted that increasing antibody dosage or antibody–antigen affinity increased immune complex formation and enhanced GC output. Beyond a point, however, a strong antiviral effect reduced antigen levels substantially, extinguishing GCs and limiting the humoral response. We found signatures of this trade-off in clinical studies. Accounting for the trade-off could be important in optimizing antibody therapy for HIV-1 remission
A local projection stabilised HHO method for the Oseen problem
No full textIn this article, we consider a local projection stabilisation for a Hybrid High-Order (HHO) approximation of the Oseen problem. We prove an existence-uniqueness result under a stronger SUPG-like norm. We improve the stability and provide error estimation in stronger norm for convection dominated Oseen problem. We also derive an optimal order error estimate under the SUPG-like norm for equal-order polynomial discretisation of velocity and pressure spaces. Numerical experiments are performed to validate the theoretical results
Understanding the structural modulations in twisted donor–acceptor–donor (D-A-D) systems for boosting Type I photosensitizing photocatalytic activity
No full textSupramolecular assemblies based on the twisted donor–acceptor–donor (D-A-D) building block Qx-Ind have been developed, which interestingly, due to the balanced angle of twist (38.28°), high intermolecular charge transfer, and crystallization induced emission (CIE) characteristics, exhibit high molar absorptivity and a long-lived “lighted” excited state at the supramolecular level. The validity of the design concept was examined by preparing CIE active D-A-D system Qx-Indaz (weak donor, low angle of twist: 35.45°), in which, due to the insertion of an additional binding site for noncovalent interactions, a drastic change in the photophysical behavior is observed. The combined spectroscopic studies of all the compounds unveil the strong impact of modulation of the angle of twist and intermolecular charge transfer upon photophysical behavior in the aggregated state. Due to the favorable photophysical behavior, the supramolecular assemblies of Qx-Ind exhibit high type I photosensitizing activity in comparison to Qx-Indaz. The superior type I photosensitizing activity of Qx-Ind assemblies is manifested in their ability to efficiently catalyze the aerobic oxidative synthesis of quinazolin-4(3H)-ones (via type I ROS) from 2-aminobenzamide and aromatic aldehydes in the absence of additional additives (base/oxidant). Unlike photocatalytic nanoassemblies reported in the literature, due to the CIE characteristics, Qx-Ind does not require preliminary preparation and could be directly introduced in the solid state to reaction media. Thus, the present work demonstrates a simple strategy of upgrading type I photosensitizing activity by improving the ground/excited state behavior of a twisted D-A-D system through modulation of the angle of twist and charge transfer characteristics
Dynamic dance of chirality and morphology: Interplay of solvent-sensitive self-assembly in topological evolution and chirality amplification
No full textThe building block Pyra-Chol has been designed and synthesized, which exhibits different achiral morphologies in good solvents, forming nanospheres in THF and nanoflowers in 1,4-dioxane. In the presence of water as a poor cosolvent, Pyra-Chol demonstrates an agnostic behavior, generating left-handed superhelices in the water:THF (80:20) solvent system. However, when the good solvent is switched to 1,4-dioxane, a change in chirality is observed in the water:1,4-dioxane (30:70) solvent system, resulting in the formation of fused nanospheres. Interestingly, when the poor cosolvent is changed from water to MCH in THF, the chiral pattern remains unchanged, but the morphology changes completely. Supported by the collective spectroscopic and microscopic analysis, the present study efficaciously demonstrates the remarkable control of hydrophobic building block over the chiral sense and also highlights the fascinating influence of good as well as poor cosolvent in supporting the distinct molecular packing
CLL-656 Multiplex ligation-dependent probe amplification (MLPA): Utility as a first line screening tool for detection of clinically relevant genomic aberrations in CLL
No full textObjective:
In Chronic lymphocytic leukemia (CLL), genomic aberrations play an important role in prognostication and treatment strategies. Current techniques based on karyotyping or FISH for detection of chromosomal abnormalities are laborious, timeconsuming and expensive. The present study was thus carried out to assess the sensitivity of Multiplex ligation-dependent probe amplification (MLPA) and to detect the frequency and association of genomic aberrations with clinical outcome in Indian CLL patients.
Patients:
CLL patients were investigated for aberrations at 13q14, 11q22, 17p13 and trisomy12 by iFISH (n=272; Metasystems, Germany) and MLPA ((n=345; MRC Holland, The Netherlands). Data for both iFISH and MLPA was available for 114 cases. The survival status was analyzed in 503 cases (OS: n=503, TTFT: n=341 (Rai stage 0-2) categorized on the basis of FISH and/or MLPA. The statistical analysis was carried out using Sigma Plot software (version 15.0).
Results:
Chromosomal aberrations were detected in a total of 69% cases with del(13q) in 32%, del(11q) in 3.7%, trisomy 12q in 12%, and del(17p) in 8% cases as sole abnormality. Concomitant presence of two abnormalities in same patient was detected in 11.5% cases. In group with coexistence of ≥2 aberrations, del(13q) was a major clone (n=45) indicating it as a primary event followed by del(11q) (n=39) and del(17p) (n=37). Comparison of MLPA results with FISH (n=114), resulted in a concordance of 89% cases; discordance was observed for 2, 2, 4 and 5 cases for trisomy 12, del(11q), del (17p) and del(13q) respectively. Del(17p) discordant cases suggest inability of MLPA in detection of ≤15% positive fraction. OS(n=503) and TTFT(n=341) were significantly lower in high risk [(del(17p)] and mid risk [(del(11q) and del(12q)] cases as compared to low risk cases [del(13q) and no abnormality)].
Discussion:
A significant proportion (69%) of Indian CLL population harbor one or the other genomic aberrations. Although the frequencies differ slightly from previous reports, the distribution pattern is similar. High concordance between MLPA and FISH indicate that MLPA represents a high-throughput, cost-effective and comprehensible technique that can be used as a first-line screening for categorization of CLL patients into prognostically different genetic subtypes