Carbon Monoxide Research Articles

Enhanced performance of 1D rod shaped Zirconium (Zr) decorated over spherical shaped Zinc oxide (ZnO) nanostructures for NO2 gas

1D rod shaped Zirconium (Zr) was decorated over spherical shaped Zinc (ZnO) nanostructures, using hydrothermal technique. The as-synthesized nanocomposites were discovered to be discriminatory in terms of sensing nitrogen dioxide (NO2) gas. The impact of doping on structural parameters, optical properties, thermal stability, morphology, and shape were explored using HR-TEM, XRD, SAED, UV–Visible, FE-SEM, FT-IR, and EDS. The doping concentration was optimized for maximal reactivity with gas. ZZ@5 nanocomposites have the highest response (70.9 %) when compared to pure ZnO, ZZ@2, ZZ@7, ZZ@5, and ZZ@10 nanocomposites. NO2 gas reaction and recovery times were 24.5 and 27.8 s, respectively. As the concentration of NO2 gas climbs from 20 to 200 ppm, the reaction to gas sensors increases. NO2 gas has higher selectivity for ZZ@5 nanocomposite than other gases (ethanol, ammonia, hydrogen, carbon monoxide, and liquefied petroleum gas). The repeatability of ZZ@5 nanocomposite was researched for 50 days and discovered to be impressive.

Examining the relationship of major air pollutants with land surface parameters and its monthly variation in Indian cities using satellite data

The relationship of land surface parameters with the air pollutants is worth exploring. The present study investigates the relation of Land Surface Temperature (LST), Normalized Difference Built-up Index (NDBI) and Normalized Difference Vegetation Index (NDVI) with six air pollutants such as Aerosol Index (AI), Carbon monoxide (CO), formaldehyde (HCHO), Sulphur Dioxide (SO2), Nitrogen dioxide (NO2) and ozone (O3) from January to December month of year 2022 in four cities situated at varying climatic zones of India. Except for O3, which exhibits lower concentration in winter and greater in summer, the air pollutants concentration showed lower values during monsoon season and higher during summer and post-monsoon seasons. The relationship of LST, NDBI and NDVI with different air pollutants were found to vary throughout the year in the four cities. The magnitude of correlation coefficient (R) was found greater for AI and NO2 as compared to other pollutants depicting greater impact of land surface parameters on concentration of AI and NO2. The surface urban cool island effect in Bikaner showed strong negative relation of LST with NO2 with magnitude of R greater than 0.41. The surface urban heat island formation in Varanasi showed strong positive correlation with the air pollutants such as AI, CO, NO2 and O3 with magnitude of R value greater than 0.61, 0.31, 0.59 and 0.32 for AI, CO, NO2 and O3, respectively. Even though, the correlation of LST with air pollutants varied with seasons and cities, NDVI showed negative correlation with most of the air pollutants in the cities except in Bikaner where vegetation content is negligible. Thus, increasing the amount of vegetation in a city can improve the air quality by lowering the quantity of air pollutants there.

Unveiling the Potential of Hydrogen in a Downsized Gasoline Direct Injection Engine Performance and Emissions Experimental Study

<div>The transportation sector’s growing focus on addressing environmental and sustainable energy concerns has led to a pursuit of the decarbonization path. In this context, hydrogen emerges as a promising zero-carbon fuel. The ability of hydrogen fuel to provide reliable performance while reducing environmental impact makes it crucial in the quest for net zero targets. This study compares gasoline and hydrogen combustion in a single-cylinder boosted direct injection (DI) spark ignition engine under various operating conditions. Initially, the engine was run over a wide range of lambda values to determine the optimal operating point for hydrogen and demonstrate lean hydrogen combustion’s benefits over gasoline combustion.</div> <div>Furthermore, a load sweep test was conducted at 2000 rpm, and the performance and emission results were compared between gasoline and optimized hydrogen combustion. An in-depth analysis was conducted by varying fuel injection time and pressure. This enabled us to explore the effects of these variables on the fuel’s performance and emissions, providing valuable insights for further optimization.</div> <div>The key findings of this study are significant. They note that hydrogen fuel allows the engine to operate under lean conditions with stable combustion up to 3.8 lambda. Lean combustion produces higher engine thermal efficiency, low cyclic variability, and near-zero NO<sub>x</sub> emissions. According to the study, hydrogen combustion produces zero emissions of hydrocarbons (HC), carbon monoxide (CO), and carbon dioxide (CO<sub>2</sub>) under a wide range of operating conditions, making it a clean and environmentally friendly fuel source. During low loading, exhaust hydrogen slip is less than 1000 ppm. This slip drops below 500 ppm as the load increases. Finally, the study proved that hydrogen is more stable than gasoline at a stoichiometric level. This suggests that hydrogen could replace gasoline in some applications, which has major implications for alternative energy.</div>

Effects of Nanoparticles on the Mechanical Properties of the Composites Prepared from Biological and Chemical Gels

Poly (N-isopropyl acrylamide) (PNIPAm) and polyacrylamide (PAAm) are widely used in antifouling research because of their non-harmful nature and their high water-absorbing capacity. In addition, hydrogels such as these two, should be investigated for their mechanical properties because their mechanical properties influence the antifouling paint containing them remaining on the surface of the vessels. In this research PAAm, PNIPAm, and kappa carrageenan (κC) doped with graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) composite gels were examined for their mechanical properties for use in antifouling paints as a potential material. For increasing the mechanical properties of composites, GO and MWCNTs are often used as doping materials. In the research described here, a compressive test was used to determine the elasticity, and the modulus was calculated. The toughness was calculated from the slope of the stress-strain curve. The PAAm, PNIPAm, and κC doped with GO and MWCNT exhibited excellent swelling and deswelling behavior and good mechanical properties as composites. The results showed that the composites’ mechanical characteristics increased with an ideal loading concentration of GO and MWCNTs. This study was inspired by our belief of a shortage of research on antifouling materials that are sensitive to the environment. We wanted to create materials that were both effective against fouling and environmentally safe by integrating the beneficial characteristics of hydrogels with potential materials inside antifouling paint. This study, we suggest, is an important step toward the development of antifouling materials with high mechanical performance that are also environmentally friendly.

Catalytic oxidation of carbon monoxide at low temperature using AuRh/TiO2 bimetallic catalysts: Effect of the synthesis method

AuRh nanoparticles supported on TiO2 P25 were synthesized by two sequential deposition methods: sequential deposition-precipitation with urea (DPU) and impregnation (IMP)-DPU. Segregated nanoparticles (RhcoreAushell ball-cup-type, and Janus-type arrangements) were observed in gold-rhodium bimetallic catalysts, but mainly ball-cup-type and Janus-type nanoparticles were found on catalysts prepared by IMP-DPU. XPS analysis of gold-rhodium bimetallic catalysts, before and after reaction allowed concluding that gold-rhodium interaction on metallic state was an important factor to avoid the oxidation of rhodium during CO oxidation. However, this effect of stabilization of the rhodium metallic phase by gold does not fully explain the promoting effect observed for some bimetallic catalysts on CO oxidation. Some structural aspects such as the atomic arrangement of the bimetallic nanoparticles and the type of active sites, determined by DRIFTS-CO, were also considered. TPR and UV–visible DR spectroscopy characterizations also showed differences in the gold-rhodium interactions.

Carbon monoxide poisoning with hippocampi lesions on MRI: cases report and literature review

BackgroundCarbon monoxide (CO) poisoning is now one of the leading causes of poisoning-related mortality worldwide. The central nervous system is the most vulnerable structure in acute CO poisoning. MRI is of great significance in the diagnosis and prognosis of CO toxic encephalopathy. The imaging features of CO poisoning are diverse. We report atypical hippocampal lesions observed on MRI in four patients after acute CO exposure.Case presentationsWe report four patients who presented to the emergency department with loss of consciousness. The diagnosis of CO poisoning was confirmed on the basis of their detailed history, physical examination and laboratory tests. Brain MRI in all of these patients revealed abnormal signal intensity in hippocampi bilaterally. They all received hyperbaric oxygen therapy. The prognosis of all four patients was poor.ConclusionHippocampi, as a relatively rare lesion on MRI of CO poisoning, is of important significance both in the early and delayed stages of acute CO poisoning. In this article, we summarize the case reports of hippocampal lesions on MRI in patients with CO poisoning in recent years, in order to provide reference for the diagnosis and prognosis of CO poisoning.

Comparison of Interstitial Lung Disease Between Antineutrophil Cytoplasmic Antibodies Positive and Negative Patients: A Retrospective Cohort Study.

Positive antineutrophil cytoplasmic antibodies (ANCAs) may occur in the setting of interstitial lung disease (ILD), with or without ANCA-associated vasculitis (AAV). We aim to compare the characteristics and clinical course of patients with ILD and positive ANCA (ANCA-ILD) to those with negative ANCA. We performed a single-center retrospective cohort study from 2018 to 2021. All patients with ILD and ANCA testing were included. Patient characteristics (symptoms, dyspnea scale, and systemic AAV), test results (pulmonary high-resolution computed tomography and pulmonary function tests), and adverse events were collected from electronic medical records. Descriptive statistics and the Fisher exact test were used to compare the outcomes of patients with ANCA-ILD to those with ILD and negative ANCA. A total of 265 patients with ILD were included. The mean follow-up duration was 69.3 months, 26 patients (9.8%) were ANCA positive, and 69.2% of those with ANCA-ILD had another autoantibody. AAV occurred in 17 patients (65.4%) with ANCA-ILD. In 29.4% of patients, AAV developed following ILD diagnosis. Usual interstitial pneumonia was the most common radiologic pattern in patients with ANCA-ILD. There was no association between ANCA status and the evolution of dyspnea,diffusing capacity of the lungs for carbon monoxide, and lung imaging. Forced vital capacity improved over time in 42% of patients with ANCA-ILD and in 17% of patients with negative ANCA (P = 0.006). Hospitalization occurred in 46.2% of patients with ANCA-ILD and in 21.8% of patients with negative ANCA (P = 0.006). Both groups had similar mortality rates. Routine ANCA testing should be considered in patients with ILD. Patients with ANCA-ILD are at risk for AAV. More research is required to better understand and manage patients with ANCA-ILD.

Operando investigation of catalytic trichloroethylene combustion over metal-doped CeO2 nanorods

The remediation of chlorinated volatile organic compounds is an intractable issue for it typically requires high temperatures and generates undesirable byproducts. This work utilized a series of representative transition metals (i.e., Cr, Cu, V) to modify the morphology, surface oxygen, and acidity of the CeO2 nanorods for trichloroethylene (TCE) treatment. A spectroscopic operando DRIFT − online GCMS reactor was introduced to examine the catalytic performance and elucidate the reaction pathway. Among them, Cr-CeO2 exhibited 50 % (T50) and 90 % (T90) TCE conversions with no byproduct at 171 °C and 241 °C, respectively. The performances of Cu-CeO2 (T90 = 391 °C), V-CeO2 (T90 = 423 °C) and CeO2 (T90 = 494 °C) were inferior to Cr-CeO2 (T90 = 241 °C), with obvious C2Cl4 generated in the TCE oxidation. It reveals that TCE adsorbed on Cr-CeO2 is dechlorinated on acidic sites and oxidized to carbonate/formate intermediates by the surface oxygen then facilely to generate carbon oxides, while TCE is adsorbed as chlorinated species (CH2ClCH2O−) on the other three catalysts which occupy the surface and require higher temperature to be oxidized. The abundant medium-strong acidic sites and surface oxygen species of Cr-CeO2 nanorods are responsible for the low-temperature activation via C-Cl cleavage on acidic sites and fast oxidation of hydrocarbon intermediates in the TCE oxidation, respectively.

Impact of Urbanization on Air Quality of Dehradun District

The increasing trend of urbanization poses a significant challenge to environmental sustainability, particularly concerning air quality. This study examines the impact of rapid urbanization on the Dehradun district land use and land cover (LULC), with the built-up area increasing from 44.2 km² to 276.5 km² between 2000-2019. The LULC analysis highlights a significant expansion of built-up areas influencing regional air quality. A comprehensive analysis of air pollutants and environmental factors spanning 2000 to 2019, utilizing TROPOMI, OMI, MODIS, MOPITT, and CHIRPS data, was also conducted. Spatial variations of air pollutants, including CO i.e. carbon monoxide, HCHO i.e. formaldehyde and NO2 i.e. nitrogen dioxide demonstrate higher concentrations in urbanized areas. Temporal variations exhibit seasonal peaks during the summer months. A 15-year trend analysis indicates a consistent rise in NO2 and HCHO, attributed to urbanization and anthropogenic activities. The correlation matrix highlights strong positive correlations among air pollutants, suggesting common sources or influences. The correlation between NO2 and CO stands at 0.652, between HCHO and CO is 0.583, and between HCHO and NO2 is 0.619. Higher correlation values of more than 0.4 are observed between the land surface temperature and pollutant concentrations, highlighting the influence of anthropogenic activities on temperature rise. In an attempt to mitigate the negative effects of uncontrolled urban sprawl on the district of Dehradun's air quality and overall environmental health, the study underscores the pressing need for sustainable urban planning. These findings contribute valuable insights for decision-makers to formulate effective strategies for environmental conservation against the unfavourable consequences of swift urbanization.

Impact of air pollution and climate change on mental health outcomes: an umbrella review of global evidence.

The impact of air pollution and climate change on mental health has recently raised strong concerns. However, a comprehensive overview analyzing the existing evidence while addressing relevant biases is lacking. This umbrella review systematically searched the PubMed/Medline, Scopus and PsycINFO databases (up to June 26, 2023) for any systematic review with meta-analysis investigating the association of air pollution or climate change with mental health outcomes. We used the R metaumbrella package to calculate and stratify the credibility of the evidence according to criteria (i.e., convincing, highly suggestive, suggestive, or weak) that address several biases, complemented by sensitivity analyses. We included 32 systematic reviews with meta-analysis that examined 284 individual studies and 237 associations of exposures to air pollution or climate change hazards and mental health outcomes. Most associations (n=195, 82.3%) involved air pollution, while the rest (n=42, 17.7%) regarded climate change hazards (mostly focusing on temperature: n=35, 14.8%). Mental health outcomes in most associations (n=185, 78.1%) involved mental disorders, followed by suicidal behavior (n=29, 12.4%), access to mental health care services (n=9, 3.7%), mental disorders-related symptomatology (n=8, 3.3%), and multiple categories together (n=6, 2.5%). Twelve associations (5.0%) achieved convincing (class I) or highly suggestive (class II) evidence. Regarding exposures to air pollution, there was convincing (class I) evidence for the association between long-term exposure to solvents and a higher incidence of dementia or cognitive impairment (odds ratio, OR=1.139), and highly suggestive (class II) evidence for the association between long-term exposure to some pollutants and higher risk for cognitive disorders (higher incidence of dementia with high vs. low levels of carbon monoxide, CO: OR=1.587; higher incidence of vascular dementia per 1 μg/m3 increase of nitrogen oxides, NOx: hazard ratio, HR=1.004). There was also highly suggestive (class II) evidence for the association between exposure to airborne particulate matter with diameter ≤10μm (PM10) during the second trimester of pregnancy and the incidence of post-partum depression (OR=1.023 per 1 μg/m3 increase); and for the association between short-term exposure to sulfur dioxide (SO2) and schizophrenia relapse (risk ratio, RR=1.005 and 1.004 per 1 μg/m3 increase, respectively 5 and 7 days after exposure). Regarding climate change hazards, there was highly suggestive (class II) evidence for the association between short-term exposure to increased temperature and suicide- or mental disorders-related mortality (RR=1.024), suicidal behavior (RR=1.012), and hospital access (i.e., hospitalization or emergency department visits) due to suicidal behavior or mental disorders (RR=1.011) or mental disorders only (RR=1.009) (RR values per 1°C increase). There was also highly suggestive (class II) evidence for the association between short-term exposure to increased apparent temperature (i.e., the temperature equivalent perceived by humans) and suicidal behavior (RR=1.01 per 1°C increase). Finally, there was highly suggestive (class II) evidence for the association between the temporal proximity of cyclone exposure and severity of symptoms of post-traumatic stress disorder (r=0.275). Although most of the above associations were small in magnitude, they extend to the entire world population, and are therefore likely to have a substantial impact. This umbrella review classifies and quantifies for the first time the global negative impacts that air pollution and climate change can exert on mental health, identifying evidence-based targets that can inform future research and population health actions.

In situ generating CO gas for destroying bacterial biofilms

The resistance and impermeability of bacterial biofilms lead to incurable infections. Interference with bacterial respiration is the key to the eradication of bacterial biofilm, but breaking the deep-tissue biofilm barrier to disrupt bacterial respiration still lacks effective means. Here, we report a hydrogel microsphere that disrupts bacterial respiration, supports in situ production of carbon monoxide gas (CO) to enhance the oxygen-depleted environment of biofilms and disrupts the bacterial respiratory chain, eliminating the bacterial biofilm ecotone (BRDMs). Under the specific interaction of α-helical structure and bacterial biofilm, BRDMs rapidly anchored and accumulated on the surface of bacterial biofilm within 8 h. Meanwhile, 8.64 μM CO gas was released in situ under an oxidative stress environment to deeply penetrate the biofilm and continuously destroy bacterial terminal oxidase, block bacterial respiration and finally disintegrate the biofilm. In a model of osteomyelitis, BRDMs disrupt the ecotopic colonization of MRSA biofilms in deep tissues, reduce inflammation, restore internal environmental homeostasis and accelerate tissue regeneration. BRDMs could be designed to remove drug-resistant biofilms from a wide range of deep tissues.

A New Functional Threshold for Minimally Invasive Lobectomy.

To assess the performance of a lower predicted postoperative (ppo) forced expiratory volume in 1 second (FEV1) or diffusion capacity of the lung for carbon monoxide (DLCO) (ppoFEV1/ppoDLCO) threshold to predict cardiopulmonary complications after minimally invasive surgery (MIS) lobectomy. Although MIS is associated with better postoperative outcomes than open surgery, MIS uses risk-assessment algorithms developed for open surgery. Moreover, several different definitions of cardiopulmonary complications are used for assessment. All patients who underwent MIS lobectomy for clinical stage I-II lung cancer from 2018 to 2022 at our institution were considered. The performance of a ppoFEV1/ppoDLCO threshold of <45% was compared against that of the current guideline threshold of <60%. Three different definitions of cardiopulmonary complications were compared: Society of Thoracic Surgeons (STS), European Society of Thoracic Surgeons (ESTS), and Berry et al. In 946 patients, the ppoFEV1/ppoDLCO threshold of <45% was associated with a higher proportion correctly classified (79% [95% CI, 76%-81%] vs. 65% [95% CI, 62%-68%]; P<0.001). The complication with the biggest difference in incidence between ppoFEV1/ppoDLCO of 45%-60% and >60% was prolonged air leak (33 [13%] vs. 34 [6%]; P<0.001). The predicted probability curves for cardiopulmonary complications were higher for the STS definition than for the ESTS or Berry definitions across ppoFEV1 and ppoDLCO values. The ppoFEV1/ppoDLCO threshold of <45% more accurately classified patients for cardiopulmonary complications after MIS lobectomy, emphasizing the need for updated risk-assessment guidelines for MIS lobectomy to optimize additional cardiopulmonary function evaluation.

Polyprodrug nanomedicine for chemiexcitation-triggered self-augmented cancer chemotherapy and gas therapy

Carbon monoxide (CO) has emerged as a potential antitumor agent by inducing the dysfunction of mitochondria and the apoptosis of cancer cells. However, it remains challenging to deliver appropriate amount of CO into tumor to ensure efficient tumor growth suppression with minimum side effects. Herein we developed a CO prodrug-loaded nanomedicine based on the self-assembly of camptothecin (CPT) polyprodrug amphiphiles. The polyprodrug nanoparticles readily dissociate upon exposure to endogenous H2O2 in the tumor, resulting in rapid release of CPT and generation of high-energy intermediate dioxetanedione. The latter can transfer the energy to neighboring CO prodrugs to activate CO production by chemiexcitation, while CPT promotes the generation of H2O2 in tumors, which in turn facilitates cascade CPT and CO release. As a result, the polyprodrug nanoparticles display remarkable tumor suppression in both subcutaneous and orthotopic breast tumor-bearing mice owing to the self-augmented CPT release and CO generation. In addition, no obvious systemic toxicity was observed in mice treated with the metal-free CO prodrug-loaded nanomedicine, suggesting the good biocompatibility of the polyprodrug nanoparticles. Our work provides new insights into the design and construction of polyprodrug nanomedicines for synergistic chemo/gas therapy.

Do air pollutants levels during the previous 48 hours predict out-of-hospital cardiac arrest incidence compared to same-day pollutants levels?

Abstract Funding Acknowledgements None. Introduction Association between air pollutants (APs) levels and out-of-hospital cardiac arrest (OHCA) at the same day of the measurements have been previously described. Whether APs levels measured during the previous 48 hours may predict OHCA occurrence is not known. Purpose To analyse whether same-day APs levels compared to APs levels during the previous 48 hours are associated with OHCA incidence. Methods OHCA admissions on five Cardiac Intensive Care Units of our city were assessed during September-2020 to December-2021. Free access data regarding particulate matter (PM10), carbon monoxide (CO), nitrogen dioxide (NO2) and ozone (O3) levels during the same period were also registered. APs measures occurred each hour daily at three different spots, delivering more than 31000 measurements. APs levels during the previous 48 hours and during the index day were compared between OHCA-free days (OHCA-Fd) and OHCA-days. Results 179 patients were included. Main demographic characteristics are shown on table 1. Daily OHCA incidence and APs mean levels/month are shown in Table 2. As shown at table 3 same-day higher NO2 and lower O3 levels were found on OHCA-days compared to OHCA-fd: 41 ±10 vs. 36 ±9 µg/m3, p=0.016 for NO2 and 45 ±13 vs. 51 ±11 µg/m3, p= 0.003 for O3. As shown on Table 2 same day mean O3 levels were also higher from April to September compared to the rest of the year (p&amp;lt;0.001). OHCA incidence was lower in this same period (p&amp;lt;0.001). There wasn’t any association between OHCA incidence and APs (NO2, O3, PM10 and CO) measured at any moment during the event's prior 48 hours. Conclusions Same-day higher NO2 and lower O3 levels were associated to a higher OHCA incidence in our city. On the other hand, association between OHCA and NO2, O3, PM10 or CO measurements during the previous 48 hours was not found in our cohort. Reducing production of NO2 (i.e., reducing fossil-fuel consumption) may reduce OHCA risk during that same day.

Estimating Inhaled Nitrogen Dioxide from the Human Biometric Response

Breathing clean air is crucial for maintaining good human health. The air we inhale can significantly impact our physical and mental well-being, influenced by parameters such as particulate matter and gases (e.g. carbon dioxide, carbon monoxide, and nitrogen dioxide). Building on previous research that explored the effects of particulate matter (PM) in specific environments, analyzed using biometric indicators and machine learning models; this work focuses on the effects and estimation of inhaled nitrogen dioxide (NO&lt;sub&gt;2&lt;/sub&gt;). This study involved a cyclist equipped with sensors to monitor various biometric parameters. In addition, an electric car following the cyclist measured the ambient NO&lt;sub&gt;2&lt;/sub&gt; levels using an onboard sensor. A total of 329 biometric variables have been taken into account, of which 320 biometric variables are cognitive responses extracted using an electroencephalogram (EEG) and 9 biometric variables are physiological responses extracted using several sensors. Inhaled NO&lt;sub&gt;2&lt;/sub&gt; levels are first estimated initially by making use of all 329 variables, then using 9 physiological responses and finally using only 6 of the 9 physiological responses. The study also uses a ranking method to pinpoint which biometric variables most significantly estimate inhaled NO&lt;sub&gt;2&lt;/sub&gt; levels. Furthermore, it investigates the linear and non-linear relationship between certain variables and inhaled NO&lt;sub&gt;2&lt;/sub&gt;. The general precision of the prediction for the data set was moderate, as indicated by the coefficient of determination (R&lt;sup&gt;2&lt;/sup&gt;) and the root mean square error (RMSE) between the true and estimated values of NO&lt;sub&gt;2&lt;/sub&gt; to be 0.35 and 5.41 ppb, respectively, in the test set. A higher accuracy in the prediction of lower values of NO&lt;sub&gt;2&lt;/sub&gt; levels was qualitatively observed using a scatter diagram and a Quantile-Quantile plot where the data were more plentiful. For more robust conclusions, additional data and refined machine learning models are necessary.

Prognostic value of pulmonary diffusing capacity for carbon monoxide and ventilation-perfusion SPECT findings in pulmonary arterial hypertension.

Reduced pulmonary diffusing capacity for carbon monoxide (DLCO) can be observed in pulmonary arterial hypertension (PAH) and associates with increased mortality. However, the prognostic value of DLCO when corrected for haemoglobin (DLCOc), an independent modifier of DLCO, remains understudied. Additionally, the prognostic role of ventilation (V)-perfusion (Q) emission computed tomography (V/Q SPECT) findings in patients with PAH, which may concurrently be performed to rule out chronic thromboembolic pulmonary hypertension, is uncertain. A retrospective cohort study was conducted on 152 patients with PAH referred to a tertiary hospital for evaluation from January 2011 to January 2020. Lung function tests, clinical data and V/Q SPECT were ascertained. Cox regression analysis was performed to evaluate the association between DLCOc, DLCO and V/Q SPECT defects at referral with all-cause mortality. In equally adjusted Cox regression analysis, each percentage increase in DLCOc % predicted (%pred) (hazard ratio (HR) 0.97; 95% CI: 0.94-0.99) and DLCO%pred (HR 0.97; 95% CI: 0.94-0.99) was similarly associated with all-cause mortality. There was no detectable difference in area under the curve for prediction of all-cause mortality by DLCOc%pred and DLCO%pred (C-index 0.71 and 0.72, respectively, P=0.85 for difference). None of the defects noted on V/Q SPECT were significantly associated with mortality, but mismatched defects were associated with lower values of DLCOc%pred and DLCO%pred. DLCOc%pred and DLCO%pred perform equally as prognostic markers in PAH, supporting the use of either metric when available for prognostic stratification.

Assessment of pharmacotherapy efficacy for the treatment of exacerbations of chronic obstructive pulmonary disease associated with viral infection

Justification. Knowledge of the differences in response to therapy between phenotypes of exacerbations of chronic obstructive pulmonary disease (COPD) is necessary to improve treatment outcomes. Objective: to determine the most effective additional pharmacological methods for virus-associated exacerbations of COPD. Material and methods. The study included patients hospitalized with exacerbations of COPD with viral (n = 60) and viral-bacterial (n = 60) infections, and a comparison group with exacerbations of COPD with bacterial infection (n = 60). The diagnosis of COPD was based on spirometric criteria, viral infection — according to the results of PCR-RV of sputum for RNA of respiratory viruses. Treatment was carried out in real clinical practice. The groups were comparable in the use of systemic glucocorticoids, short-acting bronchodilators. Dyspnea was assessed using the TDI index (primary endpoint), lung function (spirometry, diffusion capacity for carbon monoxide), exercise tolerance (6-minute walk test), length of hospital stay (secondary endpoints). The сorrelations were determined with the use of Cox proportional hazards model. Results. In the groups with virus-associated and viral-bacterial exacerbations, unlike bacterial exacerbations, the following types of treatment were associated with achieving TDI +1 (odds ratio — OR, 95 % confidence interval — CI): fixed triple combination (OR 2.69; 95 % CI 1.48–4.90; p = 0.010 and OR 2.74; 95 % CI 1.29–3.80; p = 0.031), inhalation of 3 % sodium chloride solution (OR 3.64; 95 % CI 1.45–5.42; p = 0.001 and OR 3.23; 95 % CI 2.15–5.43;\ p = 0.042), antiviral drugs (OR 2.91; 95 % CI 1.15–3.62; p = 0.009 and OR 2.76; 95 % CI 1.31–3.90; p = 0.008). As a result of treatment, an increase in DLco/Va, SpO2 after a 6-minute walk, and a decrease in the length of hospital stay were observed. Conclusion. Detection of virus-associated infections is a promising marker for determining indications for prescribing long-acting anticholinergic drugs and beta-adrenomimetics, inhaled corticosteroids, inhalations of hypertonic sodium chloride solution, and antiviral drugs for exacerbations of COPD.

Microwave-Assisted dry reforming of toluene as a model tar compound using low-cost iron catalyst for syngas clean-up

Gasification of waste feedstock such as biomass, waste plastics suffers from high tar yields during hydrogen-rich syngas production. The presence of tars result in lower quality syngas, lower syngas yields, reactor blockage, reactor down time, and costly maintenance. Therefore, removal of tar from syngas during gasification is essential. Catalytic reforming of tars via in-situ syngas cleanup is an effective way of mitigating tars. This work explores the possibility of microwave-assisted catalytic dry reforming of tars for syngas production. Due to its chemical complexity, toluene, which is one of the main tar constituents, could be used as a model tar compound. Toluene dry reforming was studied using the Fe/Al2O3 catalyst under CO2 under the temperature range of 400–700 ℃. The toluene reforming reaction was conducted using microwave and conventional thermal reactors. Under microwave irradiation, CO2 and toluene conversions are boosted to 80% at 500 ℃. Hydrogen and carbon monoxide yields were approximately five times and ten times higher in the microwave reactor at 500 ℃, respectively, compared to the productions obtained in the conventional fixed-bed reactor at 700 ℃. Filamentous carbon was also produced as a valuable side product to improve the economy of this process and such value-added carbon was only observed in the microwave reactor. Three reaction pathways were observed during microwave reaction: the toluene decomposition produces an initial hydrogen and carbon deposit on the catalyst; the formation of methane and benzene suggests toluene hydrodemethylation as a secondary reaction; and toluene hydrogenolysis forms light alkanes such as methane, and through reforming reaction under CO2 to syngas.

Cascade Self-Generation of Carbon Monoxide Triggered by Photoinduced Holes for Efficient Hypoxic Tumors Therapy.

It still remains challenging to design multifunctional therapeutic reagents for effective cancer therapy under a unique tumor microenvironment including insufficient endogenous H2O2 and O2, low pH, and a high concentration of glutathione (GSH). In this work, a CO-based phototherapeutic system triggered by photogenerated holes, which consisted of ionic liquid (IL), the CO prodrug Mn2(CO)10, and iridium(III) porphyrin (IrPor) modified carbonized ZIF-8-doped graphitic carbon nitride nanocomposite (IL/ZCN@Ir(CO)), was designed for cascade hypoxic tumors. Upon light irradiation, the photogenerated holes on IL/ZCN@Ir(CO) oxidize water into H2O2, which subsequently induces Mn2(CO)10 to release CO. Meanwhile, IrPor can convert H2O2 to hydroxyl radical (•OH) and subsequent singlet oxygen (1O2), which further triggers CO release. Moreover, the degraded MnO2 shows activity for glutathione (GSH) depletion and mimics peroxidase, leading to GSH reduction and •OH production in tumors. Thus, this strategy can in situ release high concentrations of CO and reactive oxygen species (ROS) and deplete GSH to efficiently induce cell apoptosis under hypoxic conditions, which has a high inhibiting effect on the growth of tumors, offering an attractive strategy to amplify CO and ROS generation to meet therapeutic requirements in cancer treatment.

Soil health indicators in oil palm agroforestry systems in the eastern Amazon, Brazil

Agroforestry systems (AFSs) are generally recognized for improving soil health and increasing soil carbon (C) stock. In the Amazon region, oil palm AFSs have been promoted as a productive strategy and may offer an additional benefit of recovering degraded areas. Our objective was to evaluate whether the management practices adopted in oil palm AFSs affect soil health indicators and C stock. We carried out a study in Tomé-Açu, state of Pará, eastern Amazon, through which we evaluated two oil palm AFSs that differed in species diversity: higher diversity (AFShigh) and lower diversity (AFSlow). We used a regenerating forest (FOR) to compare with the oil palm AFSs, as regenerating forests are also a model of environmental recovery in the eastern Amazon. In the 0–10, 10–20 and 20–30 cm soil layers, we evaluated chemical indicators (active acidity (pH), calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P), and aluminum (Al)), (b) physical indicators (density (SD) and stability of aggregates (AGGRE)), and (c) biological indicators (permanganate oxidizable carbon (POXC), particulate organic carbon (POC), total soil carbon (SOC content) and root stock (ROOT)). We also evaluated the total soil carbon stock (SOC stock). The values of the biological indicators in the most superficial layer, especially the C indicators, were higher in the AFSlow (C content: 1.63 ± 0.13%, POXC: 568 ± 17 mg kg−1, POC: 0.63 ± 0.10 g kg−1) and the AFShigh (C content: 1.84 ± 0.04%, POXC: 656 ± 24 mg kg−1, POC: 0.83 ± 0.06 g kg−1) than in FOR (C content: 1.35 ± 0.09%, POXC: 336 ± 10 mg kg−1, POC: 0.44 ± 0.03 g kg−1). In general, the values of chemical indicators were higher in the AFSs than in FOR, except for the Al content, which was higher in FOR than in the AFSs. The physical indicators did not show a specific pattern of variation between the AFSs and FOR; aggregate stability was higher in FOR (range throughout the soil profile: 5.57 ± 0.09 to 5.38 ± 0.24 mm) than in the AFSlow (5.41 ± 0.03 to 3.79 ± 0.07 mm) and the AFShigh (5.07 ± 0.01 to 3.79 ± 0.11 mm) in all the soil layers, and soil density was higher in the AFShigh and FOR than in the AFSlow in most subsurface layers. Therefore, oil palm AFSs improve the chemical and biological health of the soil, especially in the more superficial layers, but it does not improve the physical health of the soil when compared to the forest.