Does mask wearing affect skin health? An untargeted skin metabolomics study.

Wearing masks is used as an effective way to prevent the spread of viruses. However, the effect of wearing masks on skin health requires further assessment. In this study, a non-invasive D-squame sampling method coupled with an untargeted metabolomics analysis by liquid chromatography high-resolution mass spectrometry was developed to identify the changes in the skin metabolome caused by wearing masks. D-squame method was found to have advantages over the commonly used sterile gauze method, especially for the lipids and lipid-like molecules. A total of 356 skin metabolites were putatively identified from the stratum corneum of 10 volunteers, and 17 differential metabolites were significantly downregulated after wearing surgical masks or N95 respirators. The downregulation of metabolites such as phosphatidylethanolamine and sphingomyelin might be related to hypoxia or increased skin moisture caused by wearing masks. Changes in skin metabolomics indicated a potential risk of skin barrier disruption and skin inflammation. Intermittent removal of the masks can effectively alleviate changes in the skin metabolome.

Combined pollution effects of Cu and benzotriazole in rice (Oryza sativa L.) verified by split-root experiment.

Although the combined effect of organic ligands and heavy metals in the environment on plants have been frequently reported, their complexed interaction in plants and the physiological effects remain to be revealed. Metal complexing agent benzotriazole (BTR) has extensive environmental pollution. In this study, root-splitting experiments were designed to identify the in vivo and in vitro effects of BTR on the accumulation and translocation of Cu in rice (Oryza sativa L.), and the concentrations and translocation factor (TF) of Cu and BTR in different parts of rice were measured. In the in vitro interaction treatments, low BTR concentrations enhanced Cu uptake and lateral transport in rice, while higher levels of BTR's exposure (i.e., ≥ 100 µM) resulted in opposite effects. Differently, significant increase in the lateral transport of Cu and vertical translocation of BTR in rice presented in the in vivo interaction treatments. TF of Cu from root A to root B (TFRA-RB) increased from 0.05 to 0.272 with the BTR concentration increasing from 0 to 100 µM, and higher TF of BTR from root to shoot (TFR-S), ranging from 1.00 to 1.75, compared with single BTR exposure treatments was observed. The phytotoxicity of BTR expressed by the catalase activity was significantly alleviated by the in vivo accumulated Cu in rice.

Oxidative potential of heavy-metal contaminated soil reflects its ecological risk on earthworm.

The ecological risk of heavy metal-contaminated soil is usually evaluated by its oxidative stress on terrestrial animals, which are vulnerable to the impact of individual differences of animals and environmental conditions. Oxidative potential (OP) is the potential of particles to induce the formation of reactive oxygen species (ROS). In this study, OP of the in situ contaminated soils collected from an industrial site (i.e., 64.5-7783 mg/kg of Cu, 54.9-397 mg/kg of Pb, 278-2085 mg/kg of Zn and 0.615-121 mg/kg of Cd) were measured as 38.0-60.1 pmol/min/mg, and the water extractable Cu, Pb, Zn, and Cd in soils have been proved to contribute 89%-98% to OP. Oxidative stress in earthworms (Eisenia fetida) caused by the industrial contaminated soils can be reflected by the biomarkers such as 8-hydroxy-2'-deoxyguanosine, metallothionein, and antioxidant enzymes, and a negative correlation presents between the comprehensive biomarker response index and the OP of soils (r = -0.979, p < 0.01). This is the first time to propose a dose-response relationship between OP and oxidative stress. Metabolomic analysis also verified that the regulation of four ROS-related metabolites (i.e., l-pipecolate, 1-methylhistidine, 5-methoxytryptamine, and xanthosine) in earthworms treated with contaminated soil were directly correlated with OP values. These results indicate that OP can be used as an indicator for ecological risk assessment of heavy metal-contaminated soil, which provides a fast, stable and easily testable chemical method.

Characterization and analysis of condensates and non-condensable gases from furfural residue via fast pyrolysis in a bubbling fluidized bed reactor.

Pyrolysis of furfural residue (FR) was performed at 450-850 °C by employing a fluidized bed pyrolyzer (FBP). Addition of Kaolin and Ca-bentonite to FR considerably increased the condensate yields. The highest condensate yield (24.96 wt%) was obtained at 650 °C when Ca-bentonite was added. Fourier transform infra-red (FTIR) spectrum of pyrolysis oil (PO) indicated that catalysts promoted generation of alkene, amine, sulfate, sulfonyl chloride and oxime during pyrolysis. Gas chromatography mass spectrometry (GC-MS) demonstrated that catalysts significantly increased the content of furfural and phenol in PO and the maximum phenol content (15.36%) was achieved in PO650-3 for CaO. The quite low relative proportion (RP) of ammonia nitrogen in liquid indicated that the dominant form of nitrogen in liquid was not ammonia nitrogen. CaO had the ability to reduce H2S release, indicating significant sulfur retention capacity. The maximum RP (99.29%) of chlorine in bio-char (BC) was observed with the addition of CaO, showing its strong chlorine retention capacity.

Torrefaction subsequent to pelletization: Characterization and analysis of furfural residue and sawdust pellets.

Torrefaction integrated with pelletization has gained increasingly interest as it enhances the characteristics of fuel pellets (e.g. hydrophobicity and energy density). In current study, torrefaction of furfural residue pellets (FRPs) and sawdust pellets (SPs) was performed by employing tubular reactor furnace, and quality of pellets was compared. The characteristics of both types of pellets were significantly improved with increasing torrefaction temperature from 200 °C to 300 °C and residence time from 15 min to 30 min. The highest lower heating value of 23.78 MJ/kg and energy density ratio (1.27) for torrefied furfural residue pellets (TFRPs) and 26.76 MJ/kg and 1.46 for torrefied sawdust pellets (TSPs) were achieved at 300 °C and 120 min. Increasing torrefaction temperature and residence time, the volumetric energy densities of TFRPs increased from 25.69 (at 200 °C and 15 min) to 27.59 kJ/m3 (at 300 °C and 120 min), while those of TSPs correspondingly decreased from 20.81 to 16.69 kJ/m3. The highest true densities (i.e. 2.40 and 1.85 g/cm3) and porosities (i.e. 52 and 65 v %) of TFRPs and TSPs were achieved at 300 °C and 120 min, much higher than those of un-torrefied pellets. Moisture uptake of TFRPs and TSPs at 300 °C were only 1.4 wt% and 2.0-2.8 wt%, respectively, showing strong water-resistant ability. The crystallinity of cellulose in FRPs was found higher than that of SPs, while the crystallinity of cellulose in TFRPs was found lower than that of TSPs at same process conditions. FTIR showed that O-H bond was destroyed after torrefaction for both FRP and SP.

Comparative study for fluidized bed pyrolysis of textile dyeing sludge and municipal sewage sludge.

A comparative research was performed to evaluate the products yields and chars properties for pyrolysis of textile dyeing sludge (TDS) and municipal sewage sludge (MSS). The high fixed carbon (19.36 wt%) and low volatile (23.66 wt%) contents of TDS resulted in higher char yields and lower condensate yields. TDS char (TC) had a higher sulfur (S) retention efficiency than MSS char (MC) and CaO exhibited a great S retention effect in MC. More alkali and alkaline earth metals (e.g. Na, K, Mg and Ca) in MSS contributed to enhanced catalytic pyrolysis. In comparison to non-catalytic pyrolysis, chars from catalytic pyrolysis had lower iodine number and higher methylene blue (MB) adsorption value. MB adsorption values of MC (212.28-414.20 mg/g) were much higher than those of TC (84.32-156.07 mg/g). In contrast, heavy metals risk degrees of MC (4.20-7.56) were lower than those of TC (7.55-12.87), and heavy metals in TC and MC showed slight risks to environment.

Pyrolysis of textile dyeing sludge in fluidized bed and microwave-assisted auger reactor: Comparison and characterization of pyrolysis products.

This paper investigated fluidized bed pyrolysis (FBP) and microwave-assisted auger pyrolysis (MWAP) for treatment and disposal of textile dyeing sludge (DS), and the products were analyzed and compared. MWAP achieved higher yields of char and condensate, and lower non-condensable gas yields compared to FBP. The yields of CO2 from FBP were much higher than those from MWAP at 450-850 °C. Whereas the yields of H2, CO and CH4 from MWAP were greater than those from FBP at higher temperature (e.g. 850 °C). The maximum condensate yields of FBP and MWAP were observed at 650 °C. Pyrolysis oil of MWAP contained less of macromolecules compared to FBP. Pyridine, phenol, aniline and their derivatives were major components in MWAP oil. Pyridine was the dominant oil component at 850 °C for FBP. Most of nitrogen-, sulfur- and chlorine-containing compounds were retained in FC (FBP char) and MC (MWAP char), and higher relative proportion (RP) of nitrogen, sulfur and chlorine were observed in the condensate and non-condensable gas from MWAP in comparison with FBP. FBP and MWAP both decreased risk degrees of heavy metals compared to raw DS, and heavy metals in FC and MC posed slight risk to the environment based on national standards in China.

Microwave-assisted pyrolysis of textile dyeing sludge, and migration and distribution of heavy metals.

This study investigated the pyrolysis characteristic of textile dyeing sludge (DS) using an auger pyrolyser under microwave irradiation at different pyrolysis temperature. The migration and distribution characteristic of heavy metals and their potential ecological risks were investigated using inductively coupled plasma mass spectrometry (ICP-MS) techniques. Temperature and additives (e.g. Ca-bentonite, kaolin and CaO) significantly affected product distribution and yields. Heavy metals showed different enrichment characteristics during pyrolysis and a great percentage of the heavy metals was retained in the sludge char (SC), depending on different temperatures and additives. CaO had a strong ability for retention of S, Pb and Ni. Ca-bentonite, kaolin and CaO had considerable ability to retain Cr at 650 ℃. Ca-bentonite and CaO had positive effects on Ni retention at 450 °C and 650 °C. As was enriched at 450 °C with addition of Ca-bentonite. Cu and Zn were enriched at 450 °C and 850 °C without additives and the corresponding residue ratios (RRs) were 88.68-100%, which indicated good stability of these heavy metals during microwave pyrolysis of DS. The heavy metal contents in SC were lower than those in the national standards (CJ/T 362-2011, China) and these heavy metals showed slight potential ecological risk to the environment.

Microwave pyrolysis of textile dyeing sludge in a continuously operated auger reactor: Condensates and non-condensable gases.

This paper investigated an auger pyrolyser under microwave irradiation using textile dyeing sludge (DS) as the feedstock. Microwave power, temperature, auger speed, gas velocity and addition of catalysts were studied. In terms of ICP-MS, Cu and As concentrations in condensates, depending on pyrolysis temperatures, exceeded the wastewater discharge standard in China. The condensate and oil yields reached maximum (i.e. 12.86 wt% and 0.84 wt%, respectively) at 650 °C. The content of aromatic compounds in the oil increased as temperature increased, up to 88.38% (GC-MS area) at 750 °C. Heterocyclic aromatic compounds containing nitrogen accounted for 20%-58% of the pyrolysis oil. Addition of catalysts such as CaO and Fe decreased pyrolysis oil yield and increased the content of H2. The H2 content increased from 25.39v% without catalyst to 64.17v% with addition of 30 wt% CaO. The electricity consumption was 0.80-2.64 kWh/kg wet sludge from 450 to 750 °C and auger speed range of 1-9 rpm. Higher auger speeds and lower temperatures led to lower electricity consumption.

Microwave pyrolysis of textile dyeing sludge in a continuously operated auger reactor: Char characterization and analysis.

Textile dyeing sludge (DS) contains toxic organic and inorganic substances, and needs to be disposed by appropriate technologies. This paper investigated an auger pyrolyser under microwave irradiation for treatment and disposal of DS. Microwave power, temperature, gas and solid residence times, addition of catalysts were studied. The results showed that the char yield gradually decreased with microwave power. The residence times of solid and gas have slight effects on char yields in the temperature range of 450-750°C. Addition of CaO and Fe increased char yield, decreased non-condensable gas yield and increased H2 content. CaO promoted decomposition of DS and capture of CO2. In the meantime, CaO retained more sulfur in the solid phase compared to MWP without addition of CaO. The content of C, H and N in DS and sludge char (SC) decreased with temperature while S increased. The maximum BET (Brunauer-Emmett-Teller) surface area of 91.9m2/g was observed for SC at 550°C, consistent with Scanning Electron Microscopy (SEM) observations. X-Ray fluorescence (XRF) analysis showed existence of some heavy metals, and leaching characteristics of heavy metals in the SC meet the requirements of national standards in China and will not pose a threat to the environments.

Epileptiform Discharges and Frontal Paroxysmal EEG Abnormality Act as Predictive Marker for Subsequent Epilepsy in Children With Complex Febrile Seizures.

Using electroencephalography (EEG) for diagnosing subsequent epilepsy in children after febrile seizure (FS) is not common. The present study investigates the relationship between epileptiform discharges and subsequent epilepsy, and looks for the predictive marker for this disorder. A total of 378 children with complex FS and whose EEG showed epileptiform discharges or normal EEG were included. Development of FS was compared between those with epileptiform discharges and those with normal EEG. Risk factors were analyzed using multivariate logistic regression to clarify their effects on subsequent epilepsy. The association between generalized or focal EEG localization, and between frontal epileptiform discharges and subsequent epilepsy, were analyzed. Among 378 patients with complex FS, 51 showed epileptiform discharges. History of epilepsy, frontal seizure, number of FS, and prolonged seizure were the risk factors for epileptiform discharge. Subsequent epilepsy was significantly frequent in patients with more than 2 risk factors (odds ratio [OR] = 17; 95% confidence interval [CI] = 4.1-29.6). Prolonged seizure (OR = 4.98; 95% CI = 1.63-13.29), FS number (OR = 2.96; 95% CI = 1.23-10.51), and family history of epilepsy (OR = 2.67; 95% CI = 1.05-7.63) were significantly correlated with subsequent epilepsy. Of 9 patients with paroxysms in the frontal region, 8 (88.9%) developed epilepsy. There was concordance between frontal epileptiform discharges and subsequent epilepsy (κ = .901). In conclusion, epileptiform discharges are risk factors for subsequent epilepsy. Frontal paroxysmal EEG is a marker for subsequent epilepsy.