Multi-metal ferrite as a promising catalyst for oxygen reduction reaction in microbial fuel cell.

Improving catalytic activity of cathode with noble metal-free catalysts can significantly establish microbial fuel cells (MFCs) as a sustainable and economically affordable technology. This investigation aimed to assess the viability of utilizing tri-metal ferrite (Co0.5Cu0.5 Bi0.1Fe1.9O4) as an oxygen reduction reaction (ORR) catalyst to enhance the performance of cathode in MFCs. Trimetallic ferrite was synthesized using a sol-gel auto-combustion process. Electrochemical evaluations were conducted to assess the efficacy of as-synthesized composite as an ORR catalyst, employing electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). This evaluation revealed that the impregnation of bismuth in the Co-Cu-ferrite structure improves the reduction current response and reduces the charge transfer resistance. Further experiments were conducted to test the performance of this catalyst in an MFC. The MFC with tri-metal ferrite catalyst generated a power density of 11.44 W/m3 with 21.4% coulombic efficiency (CE), which was found to be comparable with commercially available 10% Pt/C used as cathode catalyst in MFC (power density of 12.14 W/m3 and CE of 23.1%) and substantially greater than MFC having bare carbon felt cathode without any catalyst (power density of 2.49 W/m3 and CE of 7.39%). This exceptionally inexpensive ORR catalyst has adequate merit to replace commercial costlier platinum-based cathode catalysts for upscaling MFCs.

CsPbBr3 Perovskite Crack Platelet Nanocrystals and Their Biexciton Generation.

Lead halide perovskite nanocrystals have been extensively studied in recent years as efficient optical materials for their bright and color-tunable emissions. However, these are mostly confined to their 3D nanocrystals and limited to the anisotropic nanostructures. By exploring the Cs-sublattice-induced metal(II) ion exchange with Pb(II), crack CsPbBr3 perovskite platelet nanocrystals having polar surfaces in all three directions are reported here, which remained different than reported standard square platelets. The crack platelets are also passivated with halides to enhance their brightness. Further, as these crack and passivated crack platelets have defects and polar surfaces, the exciton and biexciton generation in these platelets is investigated using femtosecond photoluminescence and transient absorption measurement at ambient as well as cryogenic temperatures, correlated with time-resolved single-particle photoluminescence spectroscopy, and compared with standard square platelets having nonpolar facets. These investigations revealed that the crack platelets and passivated crack platelets possess enhanced biexciton emission compared to square platelets due to the presence of polar surfaces in all three directions. These results provide insights into not only the design of the anisotropic nanostructures of ionic nanocrystals but also the possibility of tuning the single exciton to biexciton generation efficiency, which has potential applications in optoelectronic systems.

Application of biomimetically synthesized silver nanoparticles as cathode catalyst, quorum-quencher, and anti-biofouling agent for the performance boosting of microbial fuel cell.

A microbial fuel cell (MFC) is a cutting-edge bioelectrochemical technology, which demonstrates power and other valuables recovery while treating wastewater by cultivating electroactive microbes. However, rampant biofilm growth over the cathode surface of air cathode MFC exacerbates the oxidation-reduction reaction rate, triggering a dip in the overall performance of MFC. In this sense, biosynthesized silver nanoparticles (AgNPs) have garnered a plethora of potential applications as cathode catalysts as well as anti-biofouling agent for MFCs without harming nature. The MFC equipped with the mixture of aloe vera and algae (@5 mg/cm2) synthesized AgNPs on cathode generated a maximum power density of 66.5 mW/m2 and chemical oxygen demand removal efficiency of 85.2%, which was ca. 5.6 times and 1.2 times higher compared to control MFC operated without any catalyst on cathode. Thus, this investigation paves the way for using eco-amiable, low-cost bioderived organic compounds to assist MFC in achieving high power output and other valuables with minimal reliance on chemicals.

Waste coconut shell-derived carbon monolith as an efficient binder-free cathode for electrochemical advanced oxidation treatment of endocrine-disrupting compounds.

Discharge of endocrine-disrupting compounds such as methylparaben (MePa) into natural water bodies deteriorates the aquatic ecosystem. In this regard, electrochemical oxidation (EO) and electro-Fenton (EF) processes are acknowledged as effective methods to eliminate biorecalcitrant compounds from different wastewater matrices. In these systems, the H2O2-producing ability of carbon-based cathodes is put to advantage for producing homogenous hydroxyl radicals by simulating Fenton's reaction, which dramatically augments the contaminant removal efficiency. However, commercial carbon based cathodes are not economically affordable, especially for voluminous treatment. Hence in the present work, waste-derived carbonised coconut shell (CCS) monolith was employed as a cathode in EO and EF treatment of MePa. Almost the entire MePa with initial concentration of 10 mg/L was removed in 60 min by EO and 45 min by EF process at neutral pH, applied current density of 7.5 mA/cm2, NaCl concentration of 1.0 g/L and 10 mg/L of Fe2O3 dosing. The MePa removal efficiency of the CCS cathode-fitted system after 60 min was better than the commercial graphite plate and Ti-based mixed metal oxide employing system due to higher H2O2 electrosynthesis (H2O2 = 9.0 ± 0.6 mg/L after 60 min). Moreover, the same setup was used for treating 10 mg/L of MePa-spiked real sewage and demonstrated MePa and total organic carbon removal efficiency of 80.16 ± 2.31% and 37.42 ± 3.50%, respectively, in 45 min. Further, the CCS-mediated EF treatment achieved >90% removal of MePa for eight continuous batch cycles and recorded a current density drop of just 0.23% per cycle. The degradation pathway and toxicity assessment of the intermediates using the Ecological Structure Activity Relationships (ECOSAR) tool supported the eco-friendliness of the current treatment scheme.

Engineered nanomaterials for carbon capture and bioenergy production in microbial electrochemical technologies: A review.

The mounting threat of global warming, fuelled by industrialization and anthropogenic activities, is undeniable. In 2017, atmospheric carbon dioxide (CO2), the primary greenhouse gas, exceeded 410 ppm for the first time. Shockingly, on April 28, 2023, this figure surged even higher, reaching an alarming 425 ppm. Even though extensive research has been conducted on developing efficient carbon capture and storage technologies, most suffer from high costs, short lifespans, and significant environmental impacts. Recently, the use of engineered nanomaterials (ENM), particularly in microbial electrochemical technologies (METs), has gained momentum owing to their appropriate physicochemical properties and catalytic activity. By implementing ENM, the MET variants like microbial electrosynthesis (MES) and photosynthetic microbial fuel cells (pMFC) can enhance carbon capture efficiency with simultaneous bioenergy production and wastewater treatment. This review provides an overview of ENMs' role in carbon capture within MES and pMFC, highlighting advancements and charting future research directions.

Comparison of Imaging Severity Between Vaccinated and Unvaccinated COVID-19 Patients: Perspective of an Indian District.

BACKGROUND: Extensive vaccination drives undertaken globally helped in the fight against the coronavirus disease 2019 (COVID-19) pandemic, but different nations adopted different vaccination policies to tackle the disease. The vaccination drive in India began with the administration of two different vaccines: Covishield and Covaxin. We assessed the effect of vaccination status on imaging severity in patients with positive COVID-19 reverse transcription-polymerase chain reaction (RT-PCR)/antigen tests. METHOD: This was a single-center retrospective observation analysis carried out over three months between March 1, 2021, to May 31, 2021. Data access was provided by the District Hospital Review Board (DHRB) and the Department of Health (DOH), District Ambala, Haryana. Appropriate statistical tools were used to analyze the data. Statistical Package for Social Sciences (SPSS) 26.0 and Python 3.9 were used for statistical analysis and visualization, and a p-value of less than 0.05 was considered statistically significant. RESULTS: The total sample size of the study was 1,316, out of which 371 (28.2%) were vaccinated and 945 (71.8%) were not vaccinated. The mean age of the study participants was 49.6 ± 15.7 years. Seven hundred ninety-seven (60.6%) participants were male, while 519 (39.4%) participants were female. A statistically significant reduction was observed in the computed tomography severity score (CTSS) of the vaccinated population compared to the non-vaccinated group (χ2 = 74.3, p < 0.001). Vaccination led to a statistically significant decrease in mean CTSS across all lung lobes. CONCLUSION: Emerging COVID-19 variants challenge the effect of available vaccines, with different nations adopting different vaccination strategies to deal with the ongoing health problem. CTSS was employed as an objective marker to study the disease severity and effect of vaccination. Vaccination resulted in a significant reduction in CTSS seen on high-resolution computed tomography (HRCT) chest scans. There was a significant decrease in the incidence of severe COVID-19 pneumonia among vaccinated individuals. We need more observational data to corroborate the efficacy of vaccines presented in the randomized trials. Sharing such data between different nations can help us adopt a unifying vaccination strategy and decrease the impact of COVID-19 in subsequent disease waves.

Understanding COVID - 19 pandemic - A comprehensive Ayurvedic perspective.

Epidemics have not been new to India. Ayurveda being in the fore front of health care of those times, has recorded its valuable experiences of epidemics & termed them as Janapadodhwamsa or Maraka. It has vividly described their mechanism of Causation (Nidana), factors affecting severity and actions complicating illnesses their management and prevention. The present work uses the same model described in Samhitas which assert the superiority of host susceptibility (Nija) over External Agent/Virus (Agantuja) and uses the same principles in prevention; while adopting the Jwara model to explain and correlate with different stages of COVID - 19. It proposes management guidelines using Ahara (Nutritional Principles) and Oushadha (Medication) for different stages and subsets of patients along with their potential complications and drug interactions, utilizing the principles of host factor modification (Dosha hara) and potential broad spectrum Anti-viral (Prativisha) as envisaged by Rasa Shastra.

Data on periodontal health among elderly people in Bushland, Jharkhand, Magadha and Patna, India.

It is of interest to report data on periodontal Health among elderly people in Bushland, Jharkhand, Magadha and Patna, India. The sample comprised of a 130 elderly people. The studies device comprised of a semi-structured survey with thirteen questions. Data shows that old people in Jharkhand suffered from advanced periodontal ailment (47.6%) with easy gingivitis (33.8%). Data also shows that grownups (88.2% grownup males, 64.5% girls in Jharkhand and 34.5% grownup males and 88.9% girls in Bihar) used toothpaste and toothbrush as their primary style for tooth cleansing. These data help in providing improved dental service to rural population in India.