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Xylene isomers, including para-xylene (pX), meta-xylene (mX), ortho-xylene (oX), and ethyl benzene (EB), are important raw materials in industry. The separation of xylene isomers has been recognized as one of the "seven chemical separations to change the world". However, because of their similar physicochemical properties, totally separating four xylene isomers has remained a big challenge until now. Metal–organic frameworks (MOFs) have emerged as promising separators to achieve this goal because MOFs synergistically provide multiple mechanisms at the molecular scale. In this review, we summarize the recent progress of MOFs as separators for the separation of xylenes based on four main separation mechanisms: the molecular sieving effect, gating mechanism, thermodynamic interactions, and kinetic diffusion. We concentrate on the applications of MOFs in the field of chromatography, single-component vapor adsorption, liquid-phase competitive adsorption, breakthrough, and membrane separation. Finally, we conclude with the possible direction for designing high-performance MOF separators and briefly discuss the existing challenges in this area. [ABSTRACT FROM AUTHOR]

The real-time detection of noxious gases such as triethylamine (TEA) and xylene is important for human and environmental safety. In this work, Fe–NiO nanostructures with different doping concentrations were synthesized. By doping Fe, the gas sensitivity of NiO nanostructures was significantly improved. Gas-sensitive performance test results show that 0.93 at% Fe–NiO nanostructure-based sensors have more potential for TEA and xylene detection. The 0.93 at% Fe–NiO nanostructure-based sensor displays the highest response value of 38–50 ppm TEA at a working temperature of 220 °C and 18–50 ppm xylene at an operating temperature of 250 °C. Furthermore, the sensors show outstanding selectivity, stability and repeatability. The enhanced sensing characteristics can be ascribed to the doping of Fe with more oxygen vacancies. The as-prepared Fe–NiO nanostructures provide a novel dual-selectivity method for detection of TEA and xylene. In addition, the sensing mechanism was studied. [ABSTRACT FROM AUTHOR]

AbstractXylene substances have wide industrial and consumer uses and are currently undergoing dossier and substance evaluation under Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) for further toxicological testing including consideration of an additional neurotoxicological testing cohort to an extended one-generation reproduction toxicity (EOGRT) study. New repeated dose study data on xylenes identify the thyroid as a potential target tissue, and therefore a weight of evidence review is provided to investigate whether or not xylene-mediated changes on the hypothalamus-pituitary-thyroid (HPT) axis are secondary to liver enzymatic induction and are of a magnitude that is relevant for neurological human health concerns. Multiple published studies confirm xylene-mediated increases in liver weight, hepatocellular hypertrophy, and liver enzymatic induction via the oral or inhalation routes, including an increase in uridine 5′-diphospho-glucuronosyltransferase (UDP-GT) activity, the key step in thyroid hormone metabolism in rodents. Only minimal to slight increases in thyroid follicular cell hypertrophy have been observed in some xylene repeated dose studies, with no associated robust or consistent perturbance of thyroid hormone changes across the studies or carried through to offspring indicating adaptive homeostatic maintenance of the HPT axis. Also importantly, in vitro human cell line data from the United States Environmental Protection Agency (US EPA) Toxicity Forecasting (ToxCast) provides supporting evidence of xylene’s inability to directly perturb thyroidal functionality. A further supplemental in-depth metabolomics analysis (MetaMap®Tox) of xylene showed a tentative match to compounds that also demonstrate extra-thyroidal effects on the HPT axis as a consequence of liver enzyme induction. Lastly, the slight HPT axis changes mediated by xylene were well-below the published literature thresholds for developmental neurotoxicological outcomes established for thyroidal changes in animals and humans. In summary, the data and various lines of scientific evidence presented herein individually and collectively demonstrate that xylene’s mediated changes in the HPT axis, via a secondary extra-thyroidal MOA (i.e. liver enzyme induction), do not raise a human health concern with regards to developmental neurotoxicity. As such, the available toxicological data do not support the classification of xylene as a known or suspected endocrine disruptor, specifically through the thyroid modality, per Regulations Commission Delegated Regulation (EU) 2023/707 of 19 December 2022 amending Regulation (EC) No 1272/2008 and do not support the need for a neurotoxicological cohort evaluation in any subsequent EOGRTS. [ABSTRACT FROM AUTHOR]

Unique nanostructures contribute to optimizing gas-sensitive properties, which has been widely acknowledged in the field of gas sensing. However, the construction of nanostructures by the in situ method is still challenging. In this work, nanorod-assembled SnWO4 was fabricated directly on interdigital electrodes by a one-step aerosol-assisted chemical vapor deposition method. The xylene gas sensor was developed, featuring low detection limits and fast response. Under the operating temperature of 350°C, the detection limit of the SnWO4 sensor for xylene reaches a minimal level of 10 ppb. Meanwhile, the sensor exhibits excellent performance in response time, providing a rapid response of 2 s to 100 ppm xylene. Apart from this, the sensor also exhibits good selectivity. Among various volatile organic compound gases of the same 100 ppm at 350°C, the sensor's response to xylene (484%) is 3.6 times that of toluene and 5.3 times that of benzene. The excellent gas-sensing performance is primarily due to the unique structural properties of nanorod-assembled SnWO4. This paper holds significant research potential in the field of gas sensing, particularly for the development of high-performance xylene sensors. [ABSTRACT FROM AUTHOR]

In this work, a biofilter filled with a scoria-compost mixture to remove xylene using biofiltration is consider. The concentration of xylene in the gas and biofilin phases is the main focus of the novel model. The goal of the study is to fully comprehend how the system reacts to changing dimensioniess parameters by transforming a second-order differential equation into a dimensionless form. This is accomplished by solving the governing equation analytically using the Adomian Decomposition Method (ADM). MATLAB numerical simulations and the resulting analytical solutions for dimensionless concentrations are then compared, and a good connection is found. The paper also examines the limiting scenarios for both saturated and unsaturated kinetic reactions of xylene concentrations, offering a thorough analysis of how each parameter affects the behavior of the system. [ABSTRACT FROM AUTHOR]

Environmental pollutants, particularly volatile organic compounds (VOCs), are associated with various diseases, including atopic dermatitis (AD). However, despite numerous studies on AD, there is a lack of research on the impact of various environmental exposures on mothers and infants. This study, therefore, investigated the effects of maternal exposure to specific VOCs (toluene, xylene, and benzene) on the expression of AD-related genes in mothers and their infants. RNA expression levels and DNA methylation patterns were analyzed to examine the correlation between environmental exposures and AD. A multi-omics approach integrating gene expression and methylation data was additionally employed to gain a broader understanding of the genetic impact of VOC exposure. Network analysis revealed significant changes in gene expression associated with AD. For example, maternal exposure to toluene resulted in the upregulation of AQP10, which is linked to keratinocyte dysfunction, and in infants, the genes IL31RA and CCL20 were notably affected, both of which play critical roles in immune response and skin barrier function. In mothers exposed to xylene, the histamine receptor gene HRH1 was identified as a key player in influencing AD through its role in skin barrier recovery, while infants exhibited consistent network responses with upregulation of IL31RA and downregulation of TIGIT, reflecting a shared response across different xylene isomers. Interestingly, infants exposed to xylene isomers displayed nearly identical gene network patterns, suggesting developmental resistance to diverse environmental factors. No significant gene changes were identified in the benzene-exposed group. These findings suggest that exposure to specific VOCs may have different effects on gene expression related to AD, highlighting the complexity of how environmental factors contribute to disease development. [ABSTRACT FROM AUTHOR]

High-quality RNA is crucial in clinical diagnostics and precision medicine. Formalin-fixed and paraffin-embedded (FFPE) tissues pose a challenge due to nucleic acid fragmentation and crosslinking. In this pilot study, various commercially available techniques for extracting RNA from small FFPE samples were compared. We evaluated the KingFisher Duo automated system or the manual MagMAX FFPE DNA/RNA Ultra Kit as an RNA extraction method combined with either a xylene, d-limonene, or AutoLys M tubes deparaffinization method. Additionally, the automated Maxwell RSC RNA FFPE kit and the High Pure FFPET RNA Isolation Kit were examined using FFPE samples from inflammatory bowel disease (IBD) patients, as well as samples from ovarian, kidney, and breast cancer and the skin. The KingFisher Duo system gave a higher yield and more consistent RNA quantities, especially from small volumes of IBD samples, compared to manual extraction. The deparaffinization method also impacted results, with AutoLys M tubes proving effective in combination with the KingFisher Duo system. Conversely, the High Pure kit exhibited higher yields for larger FFPE samples. While RNA integrity is a critical factor, particularly for messenger RNA (mRNA) expression studies, its role is less prominent in microRNA (miRNA) analyses. Recognizing this, our study focused on RNA yield and purity (A260/A230) to evaluate RNA extraction methods for various sample types. These findings emphasize the importance of selecting appropriate RNA extraction methods based on sample characteristics and research goals, highlighting the performance of automated methods and the impact of deparaffinization choices. The findings contribute to refining RNA extraction for molecular biology analyses, suggesting avenues for further exploration, including cost-effectiveness under specific experimental conditions. [ABSTRACT FROM AUTHOR]

Introduction: Volatile organic compounds (VOCs) are hazardous toxic pollutants in the air, which are released from various industrial sources. Due to the adverse effects of xylene on health, the effective removal of VOCs from the air by nano sorbents is crucial. In this study, nanographene (NG) and nanographene oxide (NGO) were used as adsorbents to investigate the efficiency of xylene removal. Material and Methods: In this study, in order to investigate the absorption efficiency of nanographene and nanographene oxide after the synthesis of nano absorbents in a dynamic system, xylene vapor was produced in a chamber in pure air and stored in a Tedlar sampling bag and then transferred to the adsorbent. Subsequently, the effect of various parameters such as xylene concentration, inlet air flow rate, and absorbent mass values at 32% humidity and 25°C temperature on the absorption rate and performance of the desired absorbents was investigated. Finally, the gas chromatographic flame ion detector (GC-FID) determined the concentration of xylene in air after the adsorption-desorption process. Results: The average adsorption efficiencies for NG and NGO were found to be 96.8% and 17.5%, respectively. The characteristics of the NG and NGO adsorbents indicated that the particle size range was less than 100 nanometers. Conclusion: The results demonstrated that the adsorption efficiency of NG for the removal of xylene from the air is higher than that of NGO. The GC-MS method validated the proposed approach in real air samples.

Gasoline vapor emissions from service stations significantly affect urban atmospheric. Despite the research on the mechanisms and effectiveness of gasoline vapor removal is limited, this study innovatively investigates the static and dynamic adsorption of xylene—a typical gasoline vapor and one of the most active secondary organic aerosol (SOA) species—by commercial activated carbon (AC). The results showed that the saturation static adsorption capacity (Qe) of 12 ACs varied from 0.9 to 870.7 mg/g, which correlated with the specific surface area (SSA) and pore volume. Among them, 11# and 12# ACs were identified as the most effective adsorbents for typical gasoline vapor removal. The maximum dynamic Qe increased from 301.5 to 414.3 mg/g when the initial xylene concentration rose from 918 to 2008 mg/m3 for 11# AC, and from 201.4 to 406.2 mg/g when the initial xylene concentration increased from 589 to 2120 mg/m3 for 12# AC. These findings implied a direct correlation between higher initial xylene concentrations and greater dynamic Qe values, with static Qe values surpassing dynamic values. The adsorption kinetics simulation were analyzed by the pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetics. The kinetics results demonstrated that the PFO was more effective in characterizing the adsorption of xylene onto ACs (R2 > 0.989), indicating that the adsorption of typical gasoline vapor by ACs primarily involves physical adsorption. The findings of static/dynamic adsorption and kinetics provide valuable guidance for practical applications of gasoline vapor removal in service stations. [ABSTRACT FROM AUTHOR]

BackgroundA large body of cross-sectional studies have indicated a correlation between exposure to benzene series and increased rates of menstrual abnormalities in female workers, but these findings are confusing as evidence in the field of preventive medicine. ObjectiveTo provide a more rigorous scientific basis for early prevention of reproductive function impairment through systematic review of independent studies. MethodsA comprehensive search was conducted for scientific articles published between January 1987 and July 2022, encompassing databases such as PubMed, Medline, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang Data, and CQVIP. A meta-analysis was conducted on literature that met the stringent criteria for case-control studies, featuring well-defined and consistent datasets. A meticulous investigation was executed to ascertain the collective odds ratio (OR) linked to menstrual abnormalities, encompassing diverse categories such as component, dosage, cumulative exposure dosage, and age groups. The prevalence and corresponding risk fractions were estimated by calculating frequency distributions and attributing risk percentages (AR). ResultsA total of 53 papers of case-control studies were included in the meta-analysis, involving 27068 benzene series-exposed female workers and 22857 control female workers. During inhalation exposure to benzene series, benzene, toluene, and xylene all increased the risk of female menstrual abnormalities (OR=3.46, 95%CI: 2.79, 4.30, AR=29.37%). The OR value elevated with the increase of joint exposure concentration (OR=2.57-4.33), the OR value of the low cumulative exposure group was lower than that of the high cumulative exposure group (OR=2.81 vs 3.86, P < 0.01), and the OR value of the group aged 18 to 36 years old was higher than that of the group aged 18 to 45 years old (OR=5.83 vs 2.93, P < 0.01). The OR value discrepancy was apparent among the groups with single and multi-components of benzene, toluene, and xylene at different concentrations (OR=2.39-6.42, 95%CI: 1.26, 9.06). The symptom dimensions of menstrual abnormalities with a higher AR were abnormal menstrual volume (AR=47.12%), followed by abnormal menstrual cycle (AR=38.68%). The symptoms that were greatly influenced by the exposures were: irregular menstrual cycle (OR=3.33, 95%CI: 2.94, 3.79, AR=51.25%, n=1103), menorrhagia (OR=3.02, 95%CI: 2.76, 3.30, AR=46.73%, n=2262), dysmenorrhea (OR=3.22, 95%CI: 2.69, 3.84, AR=44.18%, n=3183), and prolonged menstrual duration (OR=2.20, 95%CI: 1.99, 2.43, AR=37.02%, n=1452). Conclusion Through inhalation exposure to benzene series, a higher concentration of combined benzene, toluene, and xylenes may increase the risk of menstrual abnormalities in female workers of childbearing age. The OR value of menstrual abnormalities is varied by chemical composition, exposure dose, cumulative exposure dose, and age. Volume and cycle of menstruation are affected by the exposure, and the most common symptoms are dysmenorrhea, menorrhagia, irregular cycle.

BackgroundWorkers engaged in benzene-exposed or benzene-containing solvent-exposed operations in China are predominantly subjected to a low concentration of benzene series compounds, and prolonged exposure to low concentrations of benzene, toluene, and xylene (BTX) may have implications for blood pressure. ObjectiveTo investigate the influence of low-concentration BTX exposure on the blood pressure of workers, aiming to provide a basis for enterprises to devise associated health management strategies to mitigate the occurrence of hypertension among workers exposed to low concentrations of BTX. MethodsUsing a cross-sectional design, 884 workers from a petroleum refining enterprise in Hainan who participated in an occupational health examination in 2022 were selected as the study population, and were divided into an exposure group of 649 workers and a control group of 235 workers based on their reporting of BTX exposure or not. Data on workplace BTX concentrations and health examinations of the study subjects were collected and questionnaires were administered. In addition, S-phenylmercapturic acid (S-PMA), hippuric acid (HA), and methyl hippuric acid (MHA, including the three isomers 2-MHA, 3-MHA, and 4-MHA) were measured in the urine of the workers using high-performance liquid chromatography-tandem triple quadrupole mass spectrometry to assess internal BTX burden. The effects of low-concentration BTX exposure on blood pressure were analyzed. ResultsIn 2022, the concentrations of benzene, toluene, and xylene of all monitoring points did not exceeded the national limits by either time-weighted average (TWA) or short-term exposure limit (STEL), indicating low-concentration BTX exposure. Regarding the internal burden of BTX, the concentrations of benzene metabolite S-PMA, toluene metabolite HA, and xylene metabolites 3-MHA and 4-MHA in the urine samples in the exposure group were higher than those in the control group (P < 0.05). The correlation analysis showed a positive correlation between urinary S-PMA concentration and diastolic blood pressure in the workers (r=0.265, P < 0.05). Differences in systolic and diastolic blood pressure distributions were statistically significant among workers grouped by sex, age, work years, educational levels, monthly income, body mass index (BMI), alcohol use, dietary oil, and types of residential address (P < 0.05). Significant differences in systolic blood pressure distribution were observed among workers by smoking status and levels of labor intensity (P < 0.05). Compared with the control group, the workers in the exposure group exhibited a significant increase in diastolic blood pressure (P < 0.05). The results of multiple linear regression showed that age, sex, and BMI had statistically significant effects on systolic blood pressure (P < 0.05), while age, work years, and BMI had statistically significant effects on diastolic blood pressure (P < 0.05). The systolic blood pressure of age > 35 years, male, overweight and obese workers was significantly higher than that of age ≤ 35 years, female, and underweight workers, and the diastolic blood pressure of age > 35 years, work years > 5 years, and obese workers was higher than age ≤35 years, ≤5 years of service, and underweight workers. Low-concentration BTX exposure was one of the main influencing factors for elevated diastolic blood pressure, and the exposed workers showed a 1.337 mmHg increase in diastolic blood pressure compared to the control group (P < 0.05). ConclusionLow-concentration BTX exposure, work years > 5 years, and obesity may elevate blood pressure among petroleum refininig workers. Regular blood pressure monitoring and enhanced health interventions for this occupational group are warranted.

Xylene and its derivatives are bulk raw materials in the chemical industry, and their oxidation products, including p‐toluic acid and terephthalic acid, are also crucial in the production of fine chemicals. Unspecific peroxygenases (UPOs) are heme‐thiolate enzymes that are capable of oxidizing diverse organic compounds. In this study, a UPO from Thielavia terrestris (TteUPO) showed the ability to oxidize p‐xylene to p‐toluic acid with >99% chemoselectivity. To address the sensitivity of TteUPO to H2O2 during the reaction, a fusion protein of TteUPO and formate oxidase from Aspergillus oryzae (AoFOx) was constructed for in situ H2O2 regeneration. Additionally, site‐directed saturation mutagenesis of TteUPO was performed, giving the mutant F63S/A155 V, which exhibited a 2.4‐fold increase in the specific activity toward p‐xylene compared with wild‐type TteUPO. The engineered fusion protein TteUPOF63S/A155V‐AoFOx achieved 3.8 mM p‐toluic acid under 8 mM p‐xylene loading, which is approximately 60‐fold higher than previously reported p‐toluic acid concentrations through bio‐oxidation. It also showed the capability to convert other monocyclic and polycyclic aromatic hydrocarbons, indicating its potential for the high‐value conversion of xylene and its derivatives. [ABSTRACT FROM AUTHOR]

The rapid and skillful detection of toxic gases is a crucial requirement for the advancement of gas sensors. In this study, we fabricated undoped and In-doped (1 %, 3 %, and 5 % by weight) ZnO films using a two-step modified SILAR deposition technique. The ethanol gas sensing properties of both undoped and In-doped ZnO films were examined across a range of operating temperatures (from room temperature, 27 °C–200 °C) and concentrations (1 ppm–50 ppm). Of all the films, those doped with 5 % Indium exhibited the most stable, reproducible, and highest response, achieving 86.27 % at 50 ppm ethanol at an operating temperature of 100 °C. Compared to the undoped ZnO films, all Indium-doped ZnO films demonstrated significantly shorter response times (17 s) and recovery times (19 s). The response of all the deposited films to various gases such as acetone, methanol, toluene, xylene, and formaldehyde was lower than their response to ethanol. The mechanism behind the enhanced sensing characteristics of the Indium-doped ZnO films is explored. Additionally, the impact of humidity on sensor performance was investigated. This study reveals that 5 % In-doped ZnO films hold great potential as materials for ethanol gas sensing applications. [ABSTRACT FROM AUTHOR]

Xylene separation is crucial but challenging, especially for the preferential separation of the intermediate‐size m‐xylene from xylene mixtures. Herein, exploiting the differences in molecular length and alkyl distribution among xylenes, we present a length‐matched metal–organic framework, formulated as Al(OH)[O2C−C4H2O−CO2], featuring an effective pore size corresponding to m‐xylene molecular length combined with multiple negative O hydrogen bond donors distribution, can serve as a molecular trap for efficient preferential separation of the intermediate‐size m‐xylene. Benchmark separation performance was achieved for separating m‐xylene from a ternary mixture of m‐xylene/o‐xylene/p‐xylene, with simultaneous record‐high m‐xylene uptake (1.3 mmol g−1) and m‐xylene/p‐xylene selectivity (5.3) in the liquid‐phase competitive adsorption. Both vapor‐ and liquid‐phase fixed‐bed tests confirmed its practical separation capability with benchmark dynamic m‐xylene/p‐xylene and m‐xylene/o‐xylene selectivities, as well as excellent regenerability. The selective and strong m‐xylene binding affinity among xylene molecules was further elucidated by simulations, validating the effectiveness of such a pore environment for the separation of intermediate‐size molecules. [ABSTRACT FROM AUTHOR]

The "storage‐oxidation" cycle is an energy‐efficient process for removing low‐concentration volatile organic compounds (VOCs). However, due to the weak interaction between BTX compounds (benzene, toluene, and xylene) and commonly used adsorbent materials, how to prevent the BTX escape prior to oxidation remains a challenge. In this work, a comprehensive study on the critical factors influencing on the "storage‐oxidation" cycling removal of BTX are investigated. The study elucidated the relationship between different zeolites and their capacity for storing BTX. It was found that the adsorption of BTX onto various zeolites is greatly impacted by the pore size of the zeolite and the volatility of BTX. Particularly, toluene and/or m‐xylene could be preferential adsorbed by Cu2+ located on the ion‐exchange sites, forming strong bonding interactions that facilitating the in‐situ thermal regeneration. Furthermore, the experimental results suggest that a synergy between Cu2+ and CuO could accelerate the catalytic oxidation of BTX. These findings offer valuable insights for designing bifunctional catalysts for the "storage‐oxidation" cycling removal of BTX. [ABSTRACT FROM AUTHOR]

This study was aimed to characterize previously isolated lactic acid bacteria Lactiplantibacillus plantarum LG138 from primate feces for its probiotic potential. The ability of the isolate to withstand different in vitro gastrointestinal stresses was assessed over a period of time i.e. at pH 2.0 and 3.0, bile salts (0.5, 1.0 and 2.0 %) and lysozyme (50,100, 150 mg/ml). Further the L. plantarum LG138 was tested for hydrophobicity, auto-aggregation and co-aggregation abilities, coexistence, exopolysaccharide production and hemolytic activity. The isolate demonstrated significant growth in the presence of different types of artificial digestive conditions (low pH, bile and lysozyme).Furthermore, oxbiledid not affect the viability of L. plantarum LG 138 cells compared to the control. The isolate L. plantarumLG138 exhibited 65.7 ± 0.32 % auto-aggregation after 24 h incubation. The hydrophobicity test found the culture moderately hydrophobic (35 to 69 %) for hexadecane and highly hydrophobic (70 to 100 %) for toluene and xylene. Moreover, it was observed to co-aggregate (66.13 ± 0.18 %) with a pathogen, Shigellaflexneri, without antagonizing other probiotic bacteria. L. plantarumLG138 was found to be able to produce exopolysaccharide and found to be non-hemolytic. These findings highlight the potential of L. plantarum LG138 as a promising probiotic candidate, suitable for incorporation into pelleted orgranulated animal feed formulations. [ABSTRACT FROM AUTHOR]

Xylene is a high production volume chemical that is widely used as a solvent and polymer precursor, and is currently undergoing substance evaluation under Registration, Evaluation, Authorization and Restriction of Chemicals (REACH). Xylenes recently received testing decisions on one-generation reproductive toxicity (EOGRT) studies with additional developmental neurotoxicity (DNT) cohorts for each of the three isomers. Xylene presents a unique opportunity to investigate the need for additional animal DNT toxicology testing because it is a legacy industrial chemical for which a significant amount of animal and human data already exists on its toxicity profile, including central nervous system effects. Therefore, to address the need for further vertebrate testing, a comprehensive weight of evidence (WOE) review of published and previously unpublished new studies of xylene substances was performed. Evidence topics included the pharmacokinetics, narcotic effects in humans and animals, narcotic mode of action (MOA), and strength of DNT signal for xylene. Pharmacokinetic data indicate minimal distribution of the unmetabolized parent compound to the fetus relative to parental brain tissue, and rapid metabolism of xylene to methyl hippuric acid (MHA), which is also rapidly excreted in both humans and animals. Xylene exposure has also resulted in transient, nonspecific neurological effects including delays in reaction time of human volunteers and reductions in motor activity of animals. This narcotic MOA for xylene occurs by the nonspecific perturbation of nervous cell membrane phospholipids, such that membrane-bound proteins and their respective functions are impaired. Furthermore, an in-depth review of the available DNT data indicates significant methodological deficiencies in several studies in the literature purported to provide evidence of a DNT concern following xylene exposure and no DNT concern reported in one reliable study. In conclusion, based on xylene's pharmacokinetics, narcotic effects on the central nervous system observed in animal and human studies, its narcotic MOA, and the lack of a robust signal from the published DNT studies, there is no trigger for the additional EOGRT study DNT cohort to be conducted for xylene. Further, the findings on narcotic effects and MOA underscore the difficulty in separating transient, acute intoxication effects via direct exposure of the offspring from investigating DNT effects (as investigated in a standard guideline (426) DNT study) in the EOGRT study, therefore producing unreliable data, which is ethically at odds with REACH and 3 R principles. [ABSTRACT FROM AUTHOR]

Anabasis articulata (Chenopodiaceae), commonly called Ajrem, is a medicinal plant of Algerian flora of arid and semiarid regions, extensively used in complementary medicine to treat diabetes, eczema, fever, and kidney diseases. The current investigation was intended to evaluate the anti-inflammatory potential of A. articulata ethanolic extract (EEAA) and its fractions that were separated using decreasing polarity solvents (hexane, chloroform, ethyl acetate, and butanol) to obtain an ethanolic extract (EEAA), a chloroform extract (ChFA), an ethyl acetate extract (EAFA), an n-butanol extract (nBFA), and an aqueous extract (AqFA). These fractions were analyzed using LC-MS-MS, whereas polyphenols, flavonoids, and tannins were evaluated using colorimetric methods. For the acute toxicity study, one oral dose of 2 and 5 g/kg was administered to mice. The in vitro anti-inflammatory properties were determined by using the egg albumin denaturation test, whereas the in vivo anti-inflammatory effect was assessed using carrageenan, croton oil, and xylene-induced edema tests. The anti-inflammatory properties of these natural compounds were assessed in silico via molecular docking simulations applying the cyclooxygenase COX2 inhibitory impact. Seven metabolites were identified: anthrone, beta-carotene, butylated hydroxyanisole, butylatedhydroxytoluene, gallic acid, myricetin, and rutin. ChFA contained the greatest quantity of polyphenols and flavonoids (497.98±0.377 mg GAE/g and 79.89±0.789 mg QE/g). While nBFA showed the highest amount of total tannins (162.89±2.103 mg TAE/g). The evaluation of the in vitro anti-inflammatory properties revealed that all fractions of A. articulata had a potent anti-inflammatory effect. No death, no toxicological symptoms, and no appreciable body weight changes between the treated and control groups were observed. Oral administration of EEAA (200 mg/kg) significantly reduced the edema induced by carrageenan, croton oil, and xylene. The molecular docking showed that beta carotene, myricetin, and rutin exhibited the most promising inhibition against COX2. Significant anti-inflammatory effects were demonstrated by A. articulata extract in vitro, in vivo, and in silico. The administration of A. ariculata ethanolic extract can be regarded as non-toxic. These findings are consistent with the plant’s traditional applications, which include therapy of anti-inflammatory illnesses. [ABSTRACT FROM AUTHOR]

The demand of 4-hydroxybenzoic acid (4-HBA) has increased due to their promising properties in the various industries such as pharmaceutical, cosmetic, and plastic sectors. Mostly 0.005 to 0.035 mol/liter of 4-HBA was observed in the waste stream or fermentation broth. Hence, this work presents a schematic study of 4-HBA separation from the aqueous phase by physical extraction method using conventional and natural solvents (CANS). The harmless and eco-friendly green solvents such as alsi (flaxseed) oil, castor oil, and conventional solvents such as diethyl carbonate, diethyl succinate, and xylene are employed in the extraction experiments. Several parameters, such as the KDHBA, %EHBA, PHBA, and the DHBA, were examined. The parameters were examined to evaluate the equilibrium for this physical extraction experiment. The obtained results showed the following trend of KDHBA and %EHBA, respectively, diethyl carbonate (0.951, 48.75%) > alsi oil (0.565, 36.12%) > diethyl succinate (0.504, 33.51%) > castor oil (0.457, 31.35%). > xylene (0.283, 22.06%). [ABSTRACT FROM AUTHOR]

Au nanoclusters with tailored photoluminescence can be obtained through controlled nanoparticle ligand interface chemistry. The present work reports molecular gold nanoclusters with tuneable photoluminescence emission from 600 to 700 nm using N,N′,N″‐trialkyl (11‐mercaptoundecyl)ammonium chloride ligands as capping‐agents. The tunability within red spectral region is regulated through specific interface chemistry between gold nanoclusters of molecular range and functional groups of the quaternary ammonium head over N,N′,N″‐trialkyl(11‐mercaptoundecyl)ammonium chloride. Combined understanding obtained from the spectroscopy, microscopy, and density functional theory studies demonstrate that the functional group specific electronic interactions at the interfaces steer the emission characteristics of "molecular" Au nanoparticles. The study clearly identifies that bulkier functional groups, i.e., triethyl, tripropyl, tributyl, and dimethyl benzene over N+ (of thiol ligand) through their steric effects minimize the particle size giving rise to tunable photoluminescence emission in red spectral region. However, the red shift seen in the emission Au nanoclusters with N‐(11‐mercaptoundecyl)‐N,N′‐dimethylbenzenammonium chloride ligand in contradiction to particle size effect is computationally proved to be due to the delocalization of electron density from benzene aromatic ring to N+ of ammonium head leading to a reduction in the HOMO‐LUMO energy gap. [ABSTRACT FROM AUTHOR]

The removal of benzene, toluene, ethylbenzene, and xylene (BTEX) from air was investigated in two similar biotrickling filters (BTFs) packed with polyurethane (PU) foam, differing in terms of inoculation procedure (BTF A was packed with pre-incubated PU discs, and BTF B was inoculated via the continuous recirculation of a liquid inoculum). The effects of white rot fungi enzyme extract addition and system responses to variable VOC loading, liquid trickling patterns, and pH were studied. Positive effects of both packing incubation and enzyme addition on biotrickling filtration performance were identified. BFF A exhibited a shorter start-up period (approximately 20 days) and lower pressure drop (75 ± 6 mm H2O) than BTF B (30 days; 86 ± 5 mm H2O), indicating the superior effects of packing incubation over inoculum circulation during the biotrickling filter start-up. The novel approach of using white rot fungi extracts resulted in fast system recovery and enhanced process performance after the BTF acidification episode. Average BTEX elimination capacities of 28.8 ± 0.4 g/(m3 h) and 23.1 ± 0.4 g/(m3 h) were reached for BTF A and BTF B, respectively. This study presents new strategies for controlling and improving the abatement of BTEX in biotrickling filters. [ABSTRACT FROM AUTHOR]

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Background Xylene, a common solvent in painting, printing, and shoemaking, enters the body through inhalation of vapors. Methods This observational analytic study aimed to examine the relationship between xylene concentration, xylene RQ, and liver function in industrial workers in Surabaya, especially in shoe industries. The chi-square method was utilized for data analysis. To ensure the validity and reliability of the study results, air and blood sampling procedures were implemented. Air sampling was conducted to measure xylene concentrations in the workplace environment, while blood samples were collected from workers to assess Serum Glutamic Oxaloacetic Transaminase (SGOT) and Serum Glutamic Pyruvate Transaminase (SGPT) levels. The study was conducted in five regions in Surabaya, namely Kalijudan, Ketintang, Jemursari, AUP, and Romokalisari. The population includes a total of 90 workers with 77 of them taken as samples using the accidental sampling method. Results The results show that there is a relationship between xylene concentration and Serum Glutamic Oxaloacetic Transaminase (SGOT) levels (p> 0.05); (r = 0,65) and there is no relationship between xylene concentrations and Serum Glutamic Pyruvate Transaminase (SGPT) levels (p> 0.05); (r = -0,12). There was no relationship between RQ and SGOT levels (p> 0.05) and there was no relationship between RQ and SGPT levels (p> 0.05). However, from the calculation of the prevalence ratio, workers with unsafe RQ (RQ>1) have a 7.09x greater chance of experiencing damage to SGOT levels and a 1.06x greater chance of experiencing damage to SGPT levels. Conclusions Xylene exposure (concentration & RQ) affects liver enzyme levels (SGOT/SGPT) in workers. Industries should consider providing nutritious food to aid xylene removal and stricter safety policies are needed. This study highlights the importance of a holistic approach to worker health and safety when dealing with hazardous chemicals.

Levels and potential toxicity of volatile organic compounds (VOCs) were analyzed in underground water from six locations near a fuel station in Okinni, Osun State, Nigeria. Samples were collected and analyzed using standard procedures. A total number of seven VOCs were detected with varying concentrations, they were: benzene, toluene, chlorobenzene, ethylbenzene, m, p-xylene, o-xylene, and dichloromethane. One-way ANOVA results showed a significant difference (p < 0.5) in VOC concentrations across locations. Most VOCs exceeded USEPA and WHO threshold values, indicating contamination likely from fuel station leachates, as suggested by the low toluene to benzene ratio (T/B < 2). Odour Hazard Index (OHI) values were below 1 in all but location 3, where m,p-xylene, and o-xylene levels were 0.921 and 1.105, respectively, implying that the water from location 3 was not safe given the odour risk assessment.. Carcinogenic risks were more significant through ingestion than dermal contact. Non-carcinogenic risk values were within safe limits except in location 3. Consequently, using the borehole water from location 3 for domestic activities could expose the people of these communities to serious health issues. Therefore, there is a need for urgent attention from the relevant authorities to safeguard the health of this populace. [ABSTRACT FROM AUTHOR]

The separation of p‐xylene from its xylene isomers (o‐xylene, m‐xylene) is a significant concern in the petrochemical industry. MFI zeolite membranes offer great potential for energy‐efficient and high‐selective xylene separation. Synthesizing ultrathin (< 1 µm) MFI zeolite membrane for high‐flux separation is highly desired but remains challenging. Herein, a novel and facile strategy for synthesizing hierarchical MFI zeolite membranes on ceramic hollow fibers from multi‐dimensionally assembled (2D@0D) seed layers is demonstrated. Owing to the rapid growth of 0D MFI seeds and the voids‐preserved growth of stacked 2D MFI seeds, the hierarchical MFI membrane synthesized for 2 h yielded an ultrathin skin layer (≈255 nm thick) and many macro‐voids within the sublayer (void fraction: 14.86%), which facilitated molecular permeation and simultaneously maintained high separation selectivity of zeolitic pores. The membrane exhibited over sevenfold higher p‐xylene permeance (2.81 × 10−7 mol m−2 s−1 Pa−1) and over threefold improved p‐/o‐xylene separation factor (1228) than the conventional MFI membrane. [ABSTRACT FROM AUTHOR]

Copyright of China Synthetic Fiber Industry is the property of Sinopec Baling Petrochemical Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to evaluate the beneficiation plant environment in a more scientific and reasonable way, this paper took the workshop environment of the beneficiation plant as the research object. This paper divided the beneficiation plant into 7 evaluation units according to its functions. The evaluation indices are dust, noise, light environment, microclimate, benzene, toluene and xylene. This paper combines the G1 method and the entropy weight method to evaluate the weight of each evaluation index, the element extension model of the concentrator working environment is established by the element analysis method, and the matter element analysis method is used to establish an evaluation index system of a beneficiation plant in East China. The results show that the evaluation level of the breaking workshop and the auxiliary facilities are unqualified, the auxiliary facility is qualified, the culling workshop, culled yard and accessory building are medium, the screening workshop and grinding workshop are good. [ABSTRACT FROM AUTHOR]

The surface states of gas sensing materials based on oxide semiconductors are closely related to their sensing dynamics. In this work, using surface engineering, p-type ZnCo2O4 architectures are prepared through a feasible hydrothermal strategy followed by subsequent annealing treatment and are applied for the detection of inert xylene gas. The as-prepared ZnCo2O4 architecture (ZCO-300) exhibits a higher response and selectivity toward xylene gas at a working temperature of 170 °C. Moreover, the ZCO-300 sensor also presents superior stability/reliability, good moisture resistance and a low detection limit of 0.1 ppm. The larger number of oxygen vacancy defects and higher specific surface area in ZCO-300 not only promote the catalytic oxidation of xylene gas by p-type semiconductor ZnCo2O4, but also provide more gas adsorption sites and surface reaction sites on sensing material surfaces, thereby endowing ZCO-300 with superior xylene gas sensing properties. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) was injected into test sheets and then dipped in a suspension of xylene and trimethylol propyl silane (95/5) containing titanium dioxide (TiO2) nanoparticles (NPs) at 65 and 85 °C for 3, 7, 10 and 15 s. TiO2 NPs aggregates coated the sheet surfaces after dipping. The camera photos and the static water contact angle (WCA) showed that the dip-coating transformed all the hydrophilic surfaces into hydrophobicity, and especially that the sheet with retention of 85 °C and 7 s exhibited superhydrophobicity, while the water droplets on the 65 °C sheets were in pinning state. The water droplets rolled off the superhydrophobic surface at tilt angles below 3°, showing self-cleaning. The retention period of 7 s was suitable, as it achieved the highest surface hydrophobicity regardless the retention temperature. The images of scanning electron microscope (SEM) and optical microscopes demonstrated the deposition of TiO2 NPs aggregates on the sheet surface and the formation of the porous structure on the surface. The combination of the aggregates with nanoscale protrusions and the pores with nanoscale pore walls constituted a hierarchical structure. The retention temperature of 65 °C made the pores shallow and wide, and the TiO2 concentration of 2% instead of 1% caused the excessive TiO2 NPs aggregates to cover the PLA substrate, reducing the WCA. The wetting models of water droplets on the surfaces of the 65 and 85 °C sticks were classified as Wenzel and Cassie states, respectively. [ABSTRACT FROM AUTHOR]

This study examined the artificial neural network (ANN) modeling of simultaneous biofiltration of methane (CH4) with two volatile organic compounds (VOCs): xylene and ethylbenzene, using an inorganic packed bed biofilter at an empty bed residence time (EBRT) of 4.5 min. Results showed that the removal efficiency (RE) of CH4 was in the range of 50 to 60% for concentrations of 1000 to 10,000 ppmv (0.6 to 6.5 g m−3), while the VOCs-REs were between 70 and 90% for X and EB concentrations in the range of 200 to 500 ppmv (0.9 to 2.2 g m−3). Artificial neural networks were used to predict and simulate the performances of the biofilter, based on a database containing previous biofiltration works. The ANN1 (architecture of 3 (input layer)-18 (hidden layer)-1 (output layer)) accurately predicted CH4 conversion at the pseudo-steadystate condition, while the ANN2 (4 (input layer)-18 (hidden layer)-2 (output layer)) predicted the simultaneous conversion of CH4 and VOCs with slightly lower accuracy than ANN1. The ANN3 (4 (input layer)-30 (hidden layer)-1 (output layer)) successfully predicted the acclimation period and final phase (CH4 concentration of 10,000 ppmv) of the biofilter but could not accurately predict the transient phases and showed differences (up to 20%) from experimental results once the CH4 concentration was changed. This study developed a decision support and prediction tool to anticipate the performance of biofilters in treating residual gases containing CH4 and VOCs, avoiding costs and delays associated with experimentation. [ABSTRACT FROM AUTHOR]

In recent years, there has been a growing interest in developing portable and personal devices for measuring air quality and surrounding pollutants, partly due to the need for ventilation in the aftermath of COVID-19 situation. Moreover, the monitoring of hazardous chemical agents is a focus for ensuring compliance with safety standards and is an indispensable component in safeguarding human welfare. Air quality measurement is conducted by public institutions with high precision but costly equipment, which requires constant calibration and maintenance by highly qualified personnel for its proper operation. Such devices, used as reference stations, have a low spatial resolution since, due to their high cost, they are usually located in a few fixed places in the city or region to be studied. However, they also have a low temporal resolution, providing few samples per hour. To overcome these drawbacks and to provide people with personalized and up-to-date air quality information, a personal device (smartwatch) based on MEMS gas sensors has been developed. The methodology followed to validate the performance of the prototype was as follows: firstly, the detection capability was tested by measuring carbon dioxide and methane at different concentrations, resulting in low detection limits; secondly, several experiments were performed to test the discrimination capability against gases such as toluene, xylene, and ethylbenzene. principal component analysis of the data showed good separation and discrimination between the gases measured. [ABSTRACT FROM AUTHOR]

The influence of decreasing the entanglement density of macromolecules on the crystallization of the β-form of polypropylene was investigated. Polypropylene with seven times less entanglement was obtained from a solution in xylene, and its properties were compared with those of fully entangled polypropylene. To obtain a high β-phase content, the polymer was nucleated using calcium pimelate. In non-isothermal crystallization studies, accelerated growth of β-crystals was found, increasing the crystallization temperature. Also, the isothermal crystallization was fastest in the nucleated, partially disentangled polypropylene. Increased growth rate of spherulites and enhanced nucleation activity in the presence of more mobile macromolecules were responsible for the high rate of melt conversion to crystals in the disentangled polypropylene. It was also observed that the equilibrium melting temperature of β-crystals is lower after disentangling macromolecules. Better conditions for crystal building after reduction of entanglements resulted in enhanced crystallization according to regime II. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Modifying with rare earth elements has been proven to be an effective means of enhancing the gas-sensing properties of oxides. In this work, Gd-In2O3 based sensor was developed, which showed high response to 100 ppm xylene gas ( = 17.8) fast response time (11 s) at 350 °C, this response value was 5.4 times higher compared to the unmodified In2O3 sensor ( =3.3). The introduction of the rare earth element not only improves the electrical properties of the sensitive material to provide a more suitable resistance but also strengthens the gas adsorption ability and the catalytic effect on the surface of the sensitive material, leading to enhanced sensing performance. [ABSTRACT FROM AUTHOR]

Introduction: Due to the lack of cadavers, anatomists across the nation are facing trouble in teaching. Plastinated specimens can be used to get around this deficiency and reliance. Aim: To assess the change in weight during plastination using melamine. Materials and Methods: A cross-sectional cadaveric study was conducted in the Department of Anatomy at GMC Kota, Rajasthan, India, using nine specimens from cadavers obtained between June 2016 and June 2017. Freshly dissected specimens from a fresh cadaver were used for plastination. The weight reduction after dehydration using acetone (three changes of seven days each), degreasing using xylene (three changes of seven days each), impregnation with a melamine-xylene mixture (10 days in a vacuum), and curing was recorded. Weight was measured using a digital weighing balance and recorded after each step. All statistical analyses were performed using Analysis of Variance (ANOVA) in MedCalc software version 22.009. Results: There was a gradual weight loss after each step except for impregnation. The percentage of mean weight after dehydration was 58.59±4.03%, after degreasing was 56.21±2.55%, after impregnation was 66.06±4.69%, and after curing was 48.26±5.39% and p-value was highly significant (

Metal–organic frameworks (MOFs) have unique potential in the field of gas sensing due to their ultra-high specific surface area and abundant mesoporous structure. In this paper, a mesoporous Co3O4 hollow polyhedron structure with high specific surface area (141.6 m2 g−1) was synthesized by annealing at the optimum temperature. The gas response of the mesoporous Co3O4 hollow polyhedron structure to volatile organic compounds such as xylene, ethanol, methanol and acetone was systematically tested. The experimental results show that the mesoporous Co3O4 hollow polyhedron structure has the highest sensitivity (21.33) and excellent stability for xylene gas, and the detection limit is low (1 ppm). The excellent sensing performance benefits from large surface area, high oxygen defect concentration and mesoporous structure. [ABSTRACT FROM AUTHOR]

Objective: This study aims to investigate the effectiveness of ultrasonic tip with and without solvent in removing gutta-perca and bioceramic sealer from the middle and apical third of the root canals. Methods: This is a true experimental study with randomized pretest-posttest control group design. Eighteen freshly extracted straight single-rooted mandibular first premolars were confirmed by CBCT and selected. The teeth were decoronated until a length of 16 ± 0.5mm. The teeth were prepared and obturated using gutta-percha and bioceramic sealer with a hydraulic condensation technique. Pre-instrumentation CBCT imaging of all teeth was carried out to obtain the initial volume of the obturation material. After incubating for 30 days, the treated teeth were randomly divided into three groups (n = 6): ultrasonic and xylene, ultrasonic and orange oil, and ultrasonic only. Post-instrumentation CBCT was carried out and the amount of obturation material removed was calculated using CT Analyser. The two-way ANOVA was used to determine the solvent and location interaction. Results: The results showed that there was no significant difference among the groups based on the treatment and location (p > 0.05). In addition, no significant interaction was found in relation to the cleanliness of the root canal (p > 0.05). Conclusion: There was no difference in the effectiveness of ultrasonic obturation material cleaning with and without endodontic solvents. Based on the results, the obturation material with the most residue is a sealer. [ABSTRACT FROM AUTHOR]

Introduction: Due to the lack of cadavers, anatomists across the nation are facing trouble in teaching. Plastinated specimens can be used to get around this deficiency and reliance. Aim: To assess the change in weight during plastination using melamine. Materials and Methods: A cross-sectional cadaveric study was conducted in the Department of Anatomy at GMC Kota, Rajasthan, India, using nine specimens from cadavers obtained between June 2016 and June 2017. Freshly dissected specimens from a fresh cadaver were used for plastination. The weight reduction after dehydration using acetone (three changes of seven days each), degreasing using xylene (three changes of seven days each), impregnation with a melamine-xylene mixture (10 days in a vacuum), and curing was recorded. Weight was measured using a digital weighing balance and recorded after each step. All statistical analyses were performed using Analysis of Variance (ANOVA) in MedCalc software version 22.009. Results: There was a gradual weight loss after each step except for impregnation. The percentage of mean weight after dehydration was 58.59±4.03%, after degreasing was 56.21±2.55%, after impregnation was 66.06±4.69%, and after curing was 48.26±5.39% and p-value was highly significant (<0.05). Conclusion: Continuous reduction in weight without distortion of anatomy resulted in lightweight plastinates which were odorfree and aesthetically pleasing. [ABSTRACT FROM AUTHOR]