Secondhand vaping exposure is an emerging public health concern that remains understudied. In this study, saliva and exhaled emissions from ENDS users (secondhand) and non-ENDS users (baseline) were collected, firsthand emissions were generated using an automated ENDS aerosol generation system programmed to simulate puffing topography profiles collected from ENDS users. Particulate concentrations and sizes along with volatile organic compounds were characterized. We revealed puffing topography metrics as potential mediators of firsthand and secondhand particle and chemical exposures, as well as metabolic and respiratory health outcomes. Particle deposition modeling revealed that while secondhand emissions displayed smaller deposited mass, total and pulmonary particle deposition fractions were higher than firsthand deposition levels, possibly due to smaller secondhand emission particle diameters. Lastly, untargeted metabolomic profiling of salivary biomarkers of lung injury due to firsthand ENDS exposures revealed potential early indicators of respiratory distress that may also be relevant in bystanders exposed to secondhand vaping scenarios. By leveraging system toxicology, we identified 10 metabolites, including leukotriene D4, that could potentially serve as biomarkers for ENDS use, exposure estimation, and the prediction of vaping-related disease. This study highlights characterization of vaping behavior is an important exposure component in advancing our understanding of potential health effects in ENDS users and bystanders.

The efficacy of low gaseous ozone concentrations (300 ppb and 400 ppb) in controlling spoilage microflora and preserving the quality of the aged Toma Piemontese PDO cheese was explored. The research integrates consumer tests, Gas Chromatography-Mass Spectrometry (GC-MS) with Solid phase Microextraction (SPME) fiber and Electronic Nose (e-nose) analysis to conduct a detailed assessment of the cheese\'s aromatic composition. Results indicate that low ozone concentrations significantly affected spoilage microflora, preserving the overall quality. Through GC-FID (Flame Ionization Detection) analysis, 22 of all identified compounds by GC-MS were quantified, including ethyl acetate (sweety), diacetyl and acetoin (buttery). Compared with the untreated sample, ozone treatments maintained the distinctive characteristics of Toma Piemontese PDO cheese, reducing the formation of off-flavors-related compounds (i.e., ethanol). Moreover, ozone-treated samples correlated with positive aroma scores given by consumers. However, sensory perception involves complex interactions among aroma compounds, highlighting the importance of advanced approaches. The utilization of a 12-sensor Quartz Microbalance (QMB) e-nose played a crucial role in identifying subtle differences in aroma, contributing to a more nuanced understanding of ozone treatments on the cheese\'s sensory profile. In conclusion, this research demonstrates the potential of ozone technology as a viable and effective method for improving the quality of aged Toma Piemontese PDO cheese.

Variants of SARS-CoV-2 pose significant challenges in public health due to their increased transmissibility and ability to evade natural immunity, vaccine protection, and monoclonal antibody therapeutics. The emergence of the highly transmissible Omicron variant and subsequent subvariants, characterized by an extensive array of over 32 mutations within the spike protein, intensifies concerns regarding vaccine evasion. In response, multiple antiviral therapeutics have received FDA emergency use approval, targeting the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) and main protease (Mpro) regions, known to have relatively fewer mutations across novel variants. In this study, we evaluated the efficacy of nirmatrelvir (PF-07321332) and other clinically significant SARS-CoV-2 antivirals against a diverse panel of SARS-CoV-2 variants, encompassing the newly identified Omicron subvariants XBB1.5 and JN.1, using live-virus antiviral assays. Our findings demonstrate that while the last Omicron subvariants exhibited heightened pathogenicity in our animal model, nirmatrelvir and other clinically relevant antivirals consistently maintained their efficacy against all tested variants, including the XBB1.5 subvariant.

Conventional screening options for colorectal cancer (CRC) detection are mainly direct visualization and invasive methods including colonoscopy and flexible sigmoidoscopy, which must be performed in a clinical setting and may be linked to adverse effects for some patients. Non-invasive CRC diagnostic tests such as computed tomography colonography and stool tests are either too costly or less reliable than invasive ones. On the other hand, volatile organic compounds (VOCs) are potentially ideal non-invasive biomarkers for CRC detection and monitoring. The present review is a comprehensive presentation of the current state-of-the-art VOC-based CRC diagnostics, with a specific focus on recent advancements in biosensor design and application. Among them, breath-based chromatography pattern analysis and sampling techniques are overviewed, along with nanoparticle-based optical and electrochemical biosensor approaches. Limitations of the currently available technologies are also discussed with an outlook for improvement in combination with big data analytics and advanced instrumentation, as well as expanding the scope and specificity of CRC-related volatile biomarkers.

Irreversible adsorption, or heel buildup, negatively impacts activated carbon performance and shortens its lifetime. This study elucidates the interconnections between flow rate and the oxygen impurity of desorption purge gas with heel buildup on beaded activated carbon (BAC). Nine thermal desorption scenarios were explored, varying nitrogen purge gas oxygen impurity levels (<5 ppmv, 10,000 ppmv, 210,000 ppm (21 %)) and flow rates (0.1, 1, 10 SLPM or 1 %, 10 %, 100 % of adsorption flow rate) during thermal desorption. Results reveal that increasing purge gas flow rate improves adsorption capacity recovery and mitigates adverse effects of purge gas oxygen impurity. Cumulative heel increased with higher purge gas oxygen impurity and lower flow rates. In the least effective regeneration scenario (0.1 SLPM N2, 21 % O2), a 32.8 wt% cumulative heel formed on BAC after five cycles, while the best-case scenario (10 SLPM N2, <5 ppmv O2) resulted in only 0.3 wt%. Comparing the pore size distributions of virgin and used BAC shows that heel initially forms in narrow micropores (<8.5Å) and later engages mesopores. Thermogravimetric analysis (TGA) showed that oxygen impurity creates high boiling point and/or strongly bound heel species. TGA confirmed that higher purge gas flow rates reduce heel amounts but encourage chemisorbed heel formation in oxygen\'s presence. These findings can guide optimization of regeneration conditions, enhancing activated carbon\'s long-term performance in cyclic adsorption processes.

Biogenic volatile organic compounds (VOCs) constitute a significant portion of gas-phase metabolites in modern ecosystems and have unique roles in moderating atmospheric oxidative capacity, solar radiation balance, and aerosol formation. It has been theorized that VOCs may account for observed geological and evolutionary phenomena during the Archaean, but the direct contribution of biology to early non-methane VOC cycling remains unexplored. Here, we provide an assessment of all potential VOCs metabolized by the last universal common ancestor (LUCA). We identify enzyme functions linked to LUCA orthologous protein groups across eight literature sources and estimate the volatility of all associated substrates to identify ancient volatile metabolites. We hone in on volatile metabolites with confirmed modern emissions that exist in conserved metabolic pathways and produce a curated list of the most likely LUCA VOCs. We introduce volatile organic metabolites associated with early life and discuss their potential influence on early carbon cycling and atmospheric chemistry.

In this study, a co-catalytic route was explored to enhance the photo-ozone catalytic degradation of volatile organic compounds (VOCs). NiCo2O4 was loaded onto the surface of CeO2 nanoparticles to create a composite catalyst (10%NiCo2O4/CeO2). The integration of NiCo2O4 onto CeO2 enhanced the interaction between the catalyst and toluene, a representative VOC, resulting in significantly increased toluene adsorption without a corresponding increase in specific surface area. This integration also improved the utilization of charge carriers and conversion of ozone to O2-. Under visible light irradiation, H2O accumulated charge carriers at 10%NiCo2O4/CeO2\'s surface, facilitating both ozone utilization and toluene adsorption. Another benefit of NiCo2O4 loading was its ability to enhance the conversion efficiency of solar energy. Consequently, the toluene removal and mineralization efficiencies of 10%NiCo2O4/CeO2 were enhanced by 182% and 309% compared to CeO2, and by 201% and 357% compared to NiCo2O4, respectively. Overall, this study demonstrated a novel co-catalyst design strategy for enhancing the photo-ozone catalytic degradation of VOCs.

A promising pollution control technology is cold plasma driven chemical processing. The plasma is a pulsed electric gas discharge inside a near atmospheric-pressure-temperature reactor. The system is energized by a continuous stream of very short high-voltage pulses. The exhaust gas to be treated flows through the reactor. The methods applied involve the development of robust cold plasma systems, industrial applications and measuring technologies. Tests of the systems were performed at many industrial sites and involved control of airborne VOC (volatile organic compound) and odor. Electrical, chemical and odor measuring data were collected with state-of-the-art methods. To explain the test data an approximate solution of global reaction kinetics of pulsed plasma chemistry was developed. It involves the Lambert function and, for convenience, a simple approximation of it. The latter shows that the amount of removal, in good approximation, is a function of a single variable. This variable is electric plasma power divided by gas flow divided by input concentration. In the results sections we show that in some cases up to 99% of volatile pollution can be removed at an acceptable energy requirement. In the final sections we look into future efficiency enhancements by implementation of (sub)nanosecond pulsed plasma and solid state high-voltage technology and by integration with catalyst technology.

In the planar heterostructure of perovskite-based solar cells (PSCs), tin oxide (SnO2) is a material that is often used as the electron transport layer (ETL). SnO2 ETL exhibits favorable optical and electrical properties in the PSC structures. Nevertheless, the open circuit voltage (VOC) depletion occurs in PSCs due to the defects arising from the high oxygen vacancy on the SnO2 surface and the deeper conduction band (CB) energy level of SnO2. In this research, a cerium (Ce) dopant was introduced in SnO2 (Ce-SnO2) to suppress the VOC loss of the PSCs. The CB minimum of SnO2 was shifted closer to that of the perovskite after the Ce doping. Besides, the Ce doping effectively passivated the surface defects on SnO2 as well as improved the electron transport velocity by the Ce-SnO2. These results enabled the power conversion efficiency (PCE) to increase from 21.1% (SnO2) to 23.0% (Ce-SnO2) of the PSCs (0.09 cm2 active area) with around 100 mV of improved VOC and reduced hysteresis. Also, the Ce-SnO2 ETL-based large area (1.0 cm2) PSCs delivered the highest PCE of 22.9%. Furthermore, a VOC of 1.19 V with a PCE of 23.3% was demonstrated by Ce-SnO2 ETL-based PSCs (0.09 cm2 active area) that were treated with 2-phenethylamine hydroiodide on the perovskite top surface. Notably, the unencapsulated Ce-SnO2 ETL-based PSC was able to maintain above 90% of its initial PCE for around 2000 h which was stored under room temperature condition (23-25 °C) with a relative humidity of 40-50%.

This review is aimed at researchers in air pollution control seeking to understand the latest advancements in volatile organic compound (VOC) removal. Implementing of plasma-catalysis technology for the removal of volatile organic compounds (VOCs) led to a significant boost in terms of degradation yield and mineralization rate with low by-product formation. The plasma-catalysis combination can be used in two distinct ways: (I) the catalyst is positioned downstream of the plasma discharge, known as the \"post plasma catalysis configuration\" (PPC), and (II) the catalyst is located in the plasma zone and exposed directly to the discharge, called \"in plasma catalysis configuration\" (IPC). Coupling these two technologies, especially for VOCs elimination has attracted the interest of many researchers in recent years. The term \"synergy\" is widely reported in their works and associated with the positive effect of the plasma catalysis combination. This review paper investigates the state of the art of newly published papers about catalysis, photocatalysis, non-thermal plasma, and their combination for VOC removal application. The focus is on understanding different synergy sources operating mutually between plasma and catalysis discussed and classified into two main parts: the effect of the plasma discharge on the catalyst and the effect of the catalyst on plasma discharge. This approach has the potential for application in air purification systems for industrial processes or indoor environments.