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Chemosphere Jul 2024Mn or Co supported CeO fiber catalysts were synthesized following a biotemplating route and evaluated in soot combustion and benzene total oxidation. The catalysts were...
Mn or Co supported CeO fiber catalysts were synthesized following a biotemplating route and evaluated in soot combustion and benzene total oxidation. The catalysts were characterized by SEM, EDX, N physisorption, FTIR-ATR, XRD, RAMAN and XPS. SEM results confirmed that the "twisted ribbon" morphology of the biotemplate was mostly maintained. XRD and Raman showed that Mn and Co cations partially insert into ceria lattice and also segregate at the surface of the fibers. XPS allowed to determine that both set of catalysts exhibit Ce and Ce species, in addition to adsorbed and lattice oxygen. Also, the average oxidation state (AOS) of surface Mn could be calculated. Compared to bare Fib Ce, the performances for both reactions were improved for the supported catalysts, except from the catalyst with lowest Mn content for soot combustion. The catalytic activity was discussed in terms of the physicochemical features of the supported catalysts.
Topics: Cerium; Oxidation-Reduction; Benzene; Catalysis; Manganese; Cobalt; Soot
PubMed: 38705410
DOI: 10.1016/j.chemosphere.2024.142247 -
Journal of Applied Toxicology : JAT May 2024In urban areas, inhalation of fine particles from combustion sources such as diesel engines causes adverse health effects. For toxicity testing, a substantial amount of...
In urban areas, inhalation of fine particles from combustion sources such as diesel engines causes adverse health effects. For toxicity testing, a substantial amount of particulate matter (PM) is needed. Conventional sampling involves collection of PM onto substrates by filtration or inertial impaction. A major drawback to those methodologies is that the extraction process can modify the collected particles and alter their chemical composition. Moreover, prior to toxicity testing, PM samples need to be resuspended, which can alter the PM sample even further. Lastly, the choice of the resuspension medium may also impact the detected toxicological responses. In this study, we compared the toxicity profile of PM obtained from two alternative sampling systems, using in vitro toxicity assays. One system makes use of condensational growth before collection in water in an impinger - BioSampler (CG-BioSampler), and the other, a Dekati® Gravimetric Impactor (DGI), is based on inertial impaction. In addition, various methods for resuspension of DGI collected PM were compared. Tested endpoints included cytotoxicity, formation of cellular reactive oxygen species, and genotoxicity. The alternative collection and suspension methods affected different toxicological endpoints. The water/dimethyl sulfoxide mixture and cell culture medium resuspended particles, along with the CG-BioSampler sample, produced the strongest responses. The water resuspended sample from the DGI appeared least toxic. CG-BioSampler collected PM caused a clear increased response in apoptotic cell death. We conclude that the CG-BioSampler PM sampler is a promising alternative to inertial impaction sampling.
PubMed: 38705171
DOI: 10.1002/jat.4616 -
Talanta Aug 2024Additive manufacturing is a technique that allows the construction of prototypes and has evolved a lot in the last 20 years, innovating industrial fabrication processes...
Additive manufacturing is a technique that allows the construction of prototypes and has evolved a lot in the last 20 years, innovating industrial fabrication processes in several areas. In chemistry, additive manufacturing has been used in several functionalities, such as microfluidic analytical devices, energy storage devices, and electrochemical sensors. Theophylline and paracetamol are important pharmaceutical drugs where overdosing can cause adverse effects, such as tachycardia, seizures, and even renal failure. Therefore, this paper aims at the development of miniaturized electrochemical sensors using 3D printing and polylactic acid-based conductive carbon black commercial filament for theophylline and paracetamol detection. Electrochemical characterizations of the proposed sensor were performed to prove the functionality of the device. Morphological characterizations were carried out, in which chemical treatment could change the surface structure, causing the improvement of the analytical signal. Thus, the detection of theophylline at a linear range of 5.00-150 μmol L with a limit of detection of 1.2 μmol L was attained, and the detection of paracetamol at a linear range of 1.00-200 μmol L with a limit of detection of 0.370 μmol L was obtained, demonstrating the proposed sensor effectively detected pharmaceutical drugs.
Topics: Acetaminophen; Soot; Electrochemical Techniques; Theophylline; Polyesters; Limit of Detection; Printing, Three-Dimensional; Miniaturization
PubMed: 38703477
DOI: 10.1016/j.talanta.2024.126154 -
Free Radical Biology & Medicine Aug 2024Carbon black nanoparticles (CBNPs) are widely distributed in the environment and are increasingly recognized as a contributor in the development of cardiovascular...
Carbon black nanoparticles (CBNPs) are widely distributed in the environment and are increasingly recognized as a contributor in the development of cardiovascular disease. A variety of cardiac injuries and diseases result from structural and functional damage to cardiomyocytes. This study explored the mechanisms of CBNPs-mediated myocardial toxicity. CBNPs were given to mice through intra-tracheal instillation and it was demonstrated that the particles can be taken up into the cardiac tissue. Exposure to CBNPs induced cardiomyocyte inflammation and apoptosis. In combination with in vitro experiments, we showed that CBNPs increased the ROS and induced mitochondria fragmentation. Functionally, CBNPs-exposed cardiomyocyte exhibited depolarization of the mitochondrial membrane potential, release of cytochrome c, and activation of pro-apoptotic BAX, thereby initiating programmed cell death. On the other hand, CBNPs impaired autophagy, leading to the inadequate removal of dysfunctional mitochondria. The excess accumulation of damaged mitochondria further stimulated NF-κB activation and triggered the NLRP3 inflammasome pathway. Both the antioxidant N-acetylcysteine and the autophagy activator rapamycin were effective to attenuate the damage of CBNPs on cardiomyocytes. Taken together, this study elucidated the potential mechanism underlying CBNPs-induced myocardial injury and provided a scientific reference for the evaluation and prevention of the CBNPs-related heart risk.
Topics: Animals; Soot; Myocytes, Cardiac; Reactive Oxygen Species; Autophagy; Mice; Nanoparticles; Apoptosis; Membrane Potential, Mitochondrial; Mitochondrial Dynamics; NLR Family, Pyrin Domain-Containing 3 Protein; Inflammasomes; NF-kappa B; Acetylcysteine; Male; Sirolimus; Mitochondria; Oxidative Stress
PubMed: 38697491
DOI: 10.1016/j.freeradbiomed.2024.04.241 -
Evaluation of biological markers for the risk assessment of carbon black in epidemiological studies.Frontiers in Public Health 2024Engineered nanomaterials (ENMs) have been suggested as being capable of promoting inflammation, a key component in the pathways associated with carcinogenesis,... (Review)
Review
BACKGROUND/OBJECTIVES
Engineered nanomaterials (ENMs) have been suggested as being capable of promoting inflammation, a key component in the pathways associated with carcinogenesis, cardiovascular disease, and other conditions. As a result, the risk assessment of biological markers as early-stage indicators has the potential to improve translation from experimental toxicologic findings to identifying evidence in human studies. The study aims to review the possible early biological changes in workers exposed to carbon black (CB), followed by an evidentiary quality evaluation to determine the predictive value of the biological markers.
METHODS
We conducted a literature search to identify epidemiological studies that assessed biological markers that were involved in the inflammatory process at early stages among workers with exposure to CB. We reviewed the studies with specific reference to the study design, statistical analyses, findings, and limitations.
RESULTS
We identified five Chinese studies that investigated the potential impact of exposure to CB on inflammatory markers, bronchial wall thickening, genomic instability, and lung function impairment in CB production workers. Of the five Chinese studies, four were cross-sectional; another study reported results at two-time points over six years of follow-up. The authors of all five studies concluded positive relationships between exposure and the inflammatory cytokine profiles. The weak to very weak correlations between biomarkers and early-stage endpoints were reported.
CONCLUSION
Most inflammatory markers failed to satisfy the proposed evidentiary quality criteria. The significance of the results of the reviewed studies is limited by the cross-sectional study design, inconsistency in results, uncertain clinical relevance, and high occupational exposures. Based on this review, the risk assessment relying on inflammatory markers does not seem appropriate at this time. Nevertheless, the novel research warrants further exploration in assessing exposure to ENMs and corresponding potential health risks in occupational settings.
Topics: Humans; Biomarkers; Soot; Risk Assessment; Occupational Exposure; Epidemiologic Studies; Inflammation
PubMed: 38689765
DOI: 10.3389/fpubh.2024.1367797 -
Scientific Reports Apr 2024This study investigates the mechanisms underlying the varied climate changes witnessed during mass extinctions in the Phanerozoic Eon. Climate shifts during mass...
This study investigates the mechanisms underlying the varied climate changes witnessed during mass extinctions in the Phanerozoic Eon. Climate shifts during mass extinctions have manifested as either predominant global cooling or predominant warming, yet the causes behind these occurrences remain unclear. We emphasize the significance of sedimentary rock temperature in comprehending these climate shifts. Our research reveals that low-temperature heating of sulfide leads to global cooling through the release of sulfur dioxide (SO), while intermediate-temperature heating of hydrocarbons and carbonates releases substantial carbon dioxide (CO), contributing to global warming. High-temperature heating additionally generates SO from sulfate, further contributing to global cooling. Different degrees of contact heating of the host rock can lead to different dominant volatile gas emissions, crucially driving either warming or cooling. Moreover, medium to high-temperature shock-heating resulting from asteroid impacts produces soot from hydrocarbons, also contributing to global cooling. Large-scale volcanic activity and asteroid impacts are both events that heat rocks, emitting the same gases and particles, causing climate changes. The findings elucidate the critical role of heating temperature and heating time in understanding major climate changes during mass extinctions.
PubMed: 38688982
DOI: 10.1038/s41598-024-60467-y -
Sensors (Basel, Switzerland) Apr 2024Due to a rising importance of the reduction of pollutant, produced by conventional energy technologies, the knowledge of pollutant forming processes during a combustion...
Due to a rising importance of the reduction of pollutant, produced by conventional energy technologies, the knowledge of pollutant forming processes during a combustion is of great interest. In this study the in-cylinder temperature, of a near series diesel engine, is examined with a minimal invasive emission spectroscopy sensor. The soot, nearly a black body radiator, emits light, which is spectrally detected and evaluated with a modified function of Planck's law. The results show a good correlation between the determined temperatures and the NO concentration, measured in the exhaust gas of the engine, during a variety of engine operating points. A standard deviation between 25 K and 49 K was obtained for the in-cylinder temperature measurements.
PubMed: 38676076
DOI: 10.3390/s24082459 -
Water Research Jun 2024The coastal urban region is generally considered an atmospheric receptor for terrestrial and marine input materials, and rainfall chemistry can trace the wet scavenging...
The coastal urban region is generally considered an atmospheric receptor for terrestrial and marine input materials, and rainfall chemistry can trace the wet scavenging process of these materials. Fast urbanization in China's east coastal areas has greatly altered the rainwater chemistry. However, the chemical variations, determinants, and sources of rainfall are unclear. Therefore, the typical coastal city of Fuzhou was selected for 1-year rainwater sampling and inorganic ions were detected to explore above problems. The findings depicted that rainwater ions in Fuzhou were slightly different from those in other coastal cities. Although NO, SO, Ca and NH dominated the rainwater ions, the marine input Cl (22 %) and Na (11 %) also contributed a considerable percentage to the rainwater ions. Large differences in ion concentrations (2∼28 times) were found in monthly scale due to the rainfall amount. Both natural and anthropogenic determinants influenced the rainwater ions in coastal cities, such as SO emission, air SO and PM content on rainwater SO, NO, and Ca, and soot & dust emission on rainwater SO, NO, indicating the vital contribution of human activities. Stoichiometry and positive matrix factorization-based sources identification indicated that atmospheric dust/particles were the primary contributor of Ca (83.3 %) and F (83.7 %), and considerable contributor of SO (39.5 %), NO (38.3 %) and K (41.5 %). Anthropogenic origins, such as urban waste volatilization and fuel combustion emission, contributed 95 % of NH, 54.5 % of NO and 41.9 % of SO, and the traffic sources contribution was relatively higher than fixed emission sources. The marine input represented the vital source of Cl (77.7 %), Na (84.9 %), and Mg (55.3 %). This work highlights the significant influence of urban human activities and marine input on rainwater chemicals and provides new insight into the material cycle between the atmosphere and earth-surface in coastal city.
Topics: Rain; China; Cities; Humans; Environmental Monitoring; Urbanization; Human Activities; Air Pollutants
PubMed: 38663214
DOI: 10.1016/j.watres.2024.121657 -
International Journal of Legal Medicine Apr 2024The use of less lethal weapons aims to mitigate civilian casualties caused by firearm use. However, due to numerous cases in which these weapons caused serious injuries,...
The use of less lethal weapons aims to mitigate civilian casualties caused by firearm use. However, due to numerous cases in which these weapons caused serious injuries, even lethal injuries, both legislation and the forensic field are interested in characterizing and regulating them better. In the forensic field, there is a lack of strong research about injury patterns of these weapons which makes it difficult to identify the type of weapon employed. In this study, the main objective was to characterize the injury pattern produced by the impact of the 9 mm P.A.K. projectile. A porcine model was used. Four different distances were studied: firm contact, 10 cm, 60 cm and 110 cm, using 3 of the more representative anatomical sites: the head, the hind leg and the ribs. The average measurement of the entrance orifice varied according to the anatomical site, being 6.67 mm wide and 6.25 mm long in the thorax, 7.3 mm wide and 8.8 mm long in the hind legs, and 7.62 mm wide and 7.54 mm long in the head. The variation in width and length measurements was not found to be directly related to the shot distance. The gunshot residues had similar characteristics to those of conventional lead projectiles, however there was more unburned powder deposit near the wounds, with a less dense soot and more dense powder tattoo. Depth varied widely regardless of tissue and firing distance, although loss of penetrating power and injury is observed as one moves away from the target.
PubMed: 38658410
DOI: 10.1007/s00414-024-03238-8 -
The Science of the Total Environment Jun 2024Airway epithelium is extraordinary vulnerable to damage owning to continuous environment exposure. Subsequent repair is therefore essential to restore the homeostasis of...
Airway epithelium is extraordinary vulnerable to damage owning to continuous environment exposure. Subsequent repair is therefore essential to restore the homeostasis of respiratory system. Disruptions in respiratory epithelial repair caused by nanoparticles exposure have been linked to various human diseases, yet implications in repair process remain incompletely elucidated. This study aims to elucidate the key stage in epithelial repair disturbed by carbon black (CB) nanoparticles, highlighting the pivotal role of ΔNp63 in mediating the epithelium repair. A competitive-like binding between CB and beta-catenin 1 (CTNNB1) to ΔNp63 is proposed to elaborate the underlying toxicity mechanism. Specifically, CB exhibits a remarkable inhibitory effect on cell proliferation, leading to aberrant airway epithelial repair, as validated in air-liquid culture. ΔNp63 drives efficient epithelial proliferation during CB exposure, and CTNNB1 was identified as a target of ΔNp63 by bioinformatics analysis. Further molecular dynamics simulation reveals that oxygen-containing functional groups on CB disrupt the native interaction of CTNNB1 with ΔNp63 through competitive-like binding pattern. This process modulates CTNNB1 expression, ultimately restraining proliferation during respiratory epithelial repair. Overall, the current study elucidates that the diminished interaction between CTNNB1 and ΔNp63 impedes respiratory epithelial repair in response to CB exposure, thereby enriching the public health risk assessment on CB-related respiratory diseases.
Topics: Soot; beta Catenin; Humans; Respiratory Mucosa; Transcription Factors; Tumor Suppressor Proteins; Cell Proliferation; Epithelial Cells; Nanoparticles
PubMed: 38653146
DOI: 10.1016/j.scitotenv.2024.172652