Abstract
Chiral nanomaterials with intrinsic chirality or spatial asymmetry at the nanoscale are currently in the limelight of both fundamental research and diverse important technological ...applications due to their unprecedented physicochemical characteristics such as intense light-matter interactions, enhanced circular dichroism, and strong circularly polarized luminescence. Herein, we provide a comprehensive overview of the state-of-the-art advances in liquid crystal-templated chiral nanomaterials. The chiroptical properties of chiral nanomaterials are touched, and their fundamental design principles and bottom-up synthesis strategies are discussed. Different chiral functional nanomaterials based on liquid-crystalline soft templates, including chiral plasmonic nanomaterials and chiral luminescent nanomaterials, are systematically introduced, and their underlying mechanisms, properties, and potential applications are emphasized. This review concludes with a perspective on the emerging applications, challenges, and future opportunities of such fascinating chiral nanomaterials. This review can not only deepen our understanding of the fundamentals of soft-matter chirality, but also shine light on the development of advanced chiral functional nanomaterials toward their versatile applications in optics, biology, catalysis, electronics, and beyond.
This paper proposes a new dynamic algorithm based on simulation approach and multi-objective optimization to solve the FJSP with transportation assignment. The objectives considered in scheduling ...jobs and transportation tasks in a flexible job shop manufacturing system include makespan, robot travel distance, time difference with due date and critical waiting time. The results obtained from the computational experiments have shown that the proposed approach is efficient and competitive.
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•AO improves joint swelling, joint score, bone and cartilage destruction in AA rats•AO inhibits inflammatory infiltration and MMPs in AA model rats•AO principally improves RA by its ...differential effect on 11 important metabolites
Atractylodes Rhizoma is one of two principal components in Ermiaosan, a well-known traditional Chinese medicine for the treatment of rheumatoid arthritis (RA). Atractylodes oil (AO) represents a potential alternative treatment for RA. The purpose of this study was to investigate the effect of AO in rats with Adjuvant Arthritis (AA) by exploration of changes in serum metabolites using gas chromatography-mass spectrometry (GC-MS). Foot thickness and arthritis score, ankle joint pathological structure, the concentrations of TNF-α, IL-1β, IL-6, IL-17 and the expression of MMPs in ankle joint tissue were measured as indicators of efficacy of treatment using AO. In addition, multivariate statistical analysis was used to identify differential production of metabolites and biomarkers, and to analyze metabolic pathways. The results demonstrate that administration of AO resulted in a good therapeutic effect in the AA rat model, with significantly improved joint swelling, reduced joint score, and inhibition of inflammation, synovial pannus hyperplasia, and bone and cartilage destruction. Furthermore, AO was found to exert its effect against rheumatoid arthritis principally by differentially affecting 11 metabolites and six metabolic pathways, predominantly related to abnormal amino acid metabolism, in addition to energy-related metabolic pathways. This study evaluated the capability of AO to effectively treat AA rats, providing a novel strategy for the treatment of RA.
Exposures to perfluoroalkyl substances (PFAS) have shown positive associations with serum lipids in previous studies. While many studies on lipids investigated associations with perfluorooctane ...sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), there are only a few studies regarding other PFAS, such as perfluorohexane sulfonic acid (PFHxS). The purpose of the current study is to investigate if associations with serum lipids were present, not only for serum PFOS and PFOA, but also for PFHxS, and if the associations with PFAS remained also in a comparison based only on residency in areas with contrasting exposure to PFAS.
1945 adults aged 20-60 were included from Ronneby, Sweden, a municipality where one out of two waterworks had been heavily contaminated from aqueous fire-fighting foams, and from a nearby control area. The exposure was categorized based on either been living in areas with contrasting PFAS exposure or based on the actual serum PFAS measurements. Regression analyses of serum lipids were fitted against serum PFAS levels, percentile groups, smooth splines and between exposed and reference areas, adjusting for age, sex and BMI.
Drinking water contamination caused high serum levels of PFOS (median 157 ng/ml) and PFHxS (median 136 ng/ml) and PFOA (median 8.6 ng/ml). These serum PFAS levels in the exposed groups were 5 to 100-fold higher than in the controls. In this population with mixed PFAS exposure, predominantly PFOS and PFHxS, PFAS exposure were positively associated with serum lipids. This was observed both when quantifying exposure as contrast between exposed and controls, and in terms of serum PFAS. Due to high correlations between each PFAS, we cannot separate them.
In conclusion, the present study provides further evidence of a causal association between PFAS and serum lipids, especially for PFHxS.
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•This study provides refined estimates of the half-life of eight PFAS, especially including the branched PFOS-isomers.•The determinants leading to shorter half-life were young age; ...better kidney function; female gender in fertile age; and possibly gut inflammation and lower gut permeability.•The result also suggested a time-dependent PFAS elimination process, with more rapid elimination in the first year after the end of exposure, than later.
Per- and polyfluoroalkyl substances (PFAS) are persistent substances with surfactant and repellent properties. Municipal drinking water contaminated with PFAS had been distributed for decades to one third of households in Ronneby, Sweden. The source was firefighting foam used in a nearby airfield since the mid-1980s. Clean water was provided from December 16, 2013.
The purpose was to estimate serum half-lives and their determinants in the study population for different PFAS.
Up to ten blood samples were collected between 2014 and 2018 from 114 participants (age 4–84 years at entry, 53% female). 19 PFAS were analysed. Linear mixed models were used to estimate the half-lives.
Eight PFAS were increased in Ronneby: perfluorooctanoic acid (PFOA), perfluoropentane sulfonate (PFPeS), perfluorohexane sulfonate (PFHxS), perfluoroheptane sulfonate (PFHpS), linear perfluorooctane sulfonate (L-PFOS) and three branched perfluorooctane sulfonates (1 m-PFOS, 3/4/5m-PFOS and 2/6m-PFOS). The mean estimated half-lives (in years) were 0.94 (95 %CI 0.86–1.02) for PFPeS, 2.47 (2.27–2.7) for PFOA, 2.67 (2.51–2.85) for 2/6m-PFOS, 2.73 (2.55–2.92) for L-PFOS, 3.43 (3.19–3.71) for 3/4/5m-PFOS, 4.52 (4.14–4.99) for PFHxS, 4.55 (4.14–5.06) for PFHpS, and 5.01 (4.56–5.55) for 1 m-PFOS.
The most important determinants of a shorter half-life were young age, and better kidney function measured by estimated glomerular filtration rate and ratio of paired urine and serum PFAS levels, followed by female sex during their fertile period aged 15–50. Markers of gut inflammation and reduced permeability i.e. zonulin and calprotectin were also possibly associated with shorter half-life. The results also suggested a time-dependent PFAS elimination process, with more rapid elimination in the first year after the end of exposure.
The half-life estimates are in line with past estimates for some PFAS such as PFOA, and the novel results for different PFOS isomers. These results provide observational support for elimination routes – renal, fecal and maternal.
•Serum PFAS levels for an exposed Swedish community are presented.•PFAS originated from AFFF result in different exposure profile.•Serum PFHxS and PFOS levels were hundredfold higher than general ...population.•Serum PFOA was higher, but to a less extent, than general population.•Shorter chain PFAS were presented in contaminated drinking water and in exposed population.
In December 2013, it was discovered that drinking water supplied to one third of the households in Ronneby, southern Sweden, was highly contaminated by PFAS (sum level >10,000 ng/L) originated from firefighting foams used at a nearby military airport.
To report serum PFAS levels of Ronneby residents participating in a biomonitoring program, and to describe the variation by age, sex and calendar period for residential exposure. In addition, a reference group living in a neighboring municipality without PFAS contaminated drinking water was examined.
Blood samples and demographic data were collected for 3297 Ronneby residents and 226 individuals from the reference group. Yearly residence addresses were available for 3086 Ronneby residents from the national population registry. Serum concentrations of PFHxS, PFOS and PFOA were determined in all participants, with additional PFHpA, PFNA and PFDA in subsets of the participants.
The population geometric means for serum PFHxS, PFOS and PFOA were 114, 135 and 6.8 ng/mL for all Ronneby residents, i.e.135, 35 and 4.5 times higher than for the reference group. Ronneby residents who resided in the area with contaminated water supply during 2005–2013 showed much higher PFAS levels in 2014 than those exposed only before 2005. Ronneby residents who never resided in the area with contaminated water supply also had higher serum PFAS levels than the reference group. All three PFAS were highly correlated (rs > 0.9 for each pair). Serum PFAS levels were lowest in teenage years and then increased with age. Adult females had lower PFAS levels on average than males under the age of 60 but higher above 60.
The results reveal high serum PFAS levels dominated by PFHxS and PFOS in the Ronneby residents highly exposed to PFAS originated from firefighting foams. The PFAS exposure in Ronneby permits studies of associations to a range of health parameters, as well as studies of the toxicokinetics of PFAS exposure.
•A registry cohort with high drinking water exposure to PFHxS and PFOS was examined.•A twofold increased risk for PCOS was found in the highest exposure group.•The risk for uterine leiomyoma was ...nominally elevated.•No increased risk for endometriosis was observed.
Perfluorinated substances (PFAS) are chemicals with endocrine disruptive properties that may interfere with the female reproductive system. However, few studies have explored the association between benign gynecological diseases and high PFAS exposure.
The aim of this study was to investigate the possible associations between PFAS exposure and subsequent diagnosis of polycystic ovarian syndrome (PCOS), uterine leiomyoma (fibroids), and endometriosis in a cohort exposed to PFAS through drinking water.
In 2013, high levels (with sum of PFAS above 10,000 ng/L), dominated by perfluorooctanesulfonic acid (PFOS) and perfluorohexane sulfonic acid (PFHxS), were found in the drinking water from one of the two waterworks in Ronneby, Sweden. The contamination came from firefighting foams used at a nearby airfield. Females of all ages (n = 29,106) who had ever resided in the municipality between 1985 and 2013 formed a cohort. Individual exposure was assessed based on municipality waterworks distribution data linked to annual residential address data; 27% of the females had ever lived at an address with PFAS-contaminated water. Gynecological health outcomes were retrieved from the Swedish National Patient Register. The Cox proportional hazards model was used to estimate the association between exposure and each diagnosis.
There were in all 161 cases of PCOS, 1,122 cases of uterine leiomyoma, and 373 cases of endometriosis. In women aged 20–50 years (n = 18,503), those with the highest estimated PFAS exposure had increased hazard ratios (HR) for PCOS (HR = 2.18; 95% confidence interval (CI) 1.43, 3.34) and uterine leiomyoma (HR = 1.28; 95% CI 0.95, 1.74). No increased HR for endometriosis was found (HR = 0.74; 95% CI 0.42, 1.29).
Exposure to high levels of PFAS in drinking water was associated with increased risk of PCOS and possibly uterine leiomyoma, but not endometriosis. The findings for PCOS are consistent with prior studies reporting positive associations between PCOS and PFAS exposure at background levels.
Propane dehydrogenation (PDH) is an industrial technology for direct propylene production which has received extensive attention in recent years. Nevertheless, existing non-oxidative dehydrogenation ...technologies still suffer from the thermodynamic equilibrium limitations and severe coking. Here, we develop the intensified propane dehydrogenation to propylene by the chemical looping engineering on nanoscale core-shell redox catalysts. The core-shell redox catalyst combines dehydrogenation catalyst and solid oxygen carrier at one particle, preferably compose of two to three atomic layer-type vanadia coating ceria nanodomains. The highest 93.5% propylene selectivity is obtained, sustaining 43.6% propylene yield under 300 long-term dehydrogenation-oxidation cycles, which outperforms an analog of industrially relevant K-CrO
/Al
O
catalysts and exhibits 45% energy savings in the scale-up of chemical looping scheme. Combining in situ spectroscopies, kinetics, and theoretical calculation, an intrinsically dynamic lattice oxygen "donator-acceptor" process is proposed that O
generated from the ceria oxygen carrier is boosted to diffuse and transfer to vanadia dehydrogenation sites via a concerted hopping pathway at the interface, stabilizing surface vanadia with moderate oxygen coverage at pseudo steady state for selective dehydrogenation without significant overoxidation or cracking.
While hydro turbines generate over 40% of the world’s total renewable energy, these traditional turbines present a great environmental concern due to the potential of their sharp blades to damage ...aquatic lives and ecology, along with their harmful noise and vibration during operation. One effective solution to these environmental issues is to substantially increase the skew of these blades, which would result in a much safer blade operation for aquatic animals (such as fish, etc.) and a substantial reduction in noise and vibration. Adding skew to turbine rotors is known to reduce cavitation and noise, and hence, to mitigate the environmental impact on underwater fauna and flora. However, adding skew will compromise the power performance of the turbines. This study aimed to identify the effect of rotor skew on the hydrodynamic power performance of a series of horizontal-axis turbine rotors that were manufactured using 3D printing technology and tested in a towing tank. The diameter of the turbine rotor model was 0.3 m and the skewed angle contained positive and negative angles of 45, 60 and 90 degrees along with a non-skewed rotor. This study was conducted to analyze the hydrodynamics of a turbine rotor with different skew angles and a 0-degree skewed rotor. Various tip speed ratios, ranging from 2.3 to 4.3, were set in accordance with the RPM and the carriage speed. Gain and filter were applied to boost the signal, and post-calibration was conducted. The results show that (1) the non-skewed rotor had the highest power coefficient; (2) the rotor with a skew angle of 45 degrees had the lowest power loss, at 6.97%, compared with the zero-skew rotor blades; (3) while the larger the skew, the more loss in power production efficiency, the rotor with a negative 90-degree skewed angle had the largest power loss, 31.42%. It was then concluded that, based on the results and analysis, (1) to achieve the greatest reduction in noise and vibration, the rotor with a skew angle of 90 degrees would be the best choice, and (2) to mitigate noise/vibration and efficiency due to skew, the rotor with a skewed angle of 45 degrees would be the best design choice.
•MiRNA expression in a cohort highly exposed to perfluoroalkyl substances (PFAS)•MiR-101-3p, miR-144-3p and miR-19a-3p were downregulated with increased serum PFAS.•In silico analyses showed 7 target ...genes for these 3 miRNAs to be annotated to PFAS.•Ingenuity pathway analyses suggest these miRNAs associated to several health effects.•This study propose epigenetic mechanisms as a mode of action of PFAS toxicity.
Perfluoroalkyl substances (PFAS) are widespread synthetic substances with various adverse health effects. Not much is known about the modes of action of PFAS toxicity, but one likely mechanism is alteration of microRNA expression.
To investigate whether PFAS exposure is associated with altered microRNA expression in serum.
We selected women from the Ronneby cohort, with high exposure to perfluorooctane sulfonic acid (PFOS) and perfluorohexane sulfonic acid (PFHxS), emanating from drinking water contaminated by firefighting foam, and a control group of women from a neighbouring municipality without drinking water contamination. Serum levels of PFAS were analysed using LC/MS/MS. High coverage microRNA expression was analysed by next generation sequencing (NGS) in 53 individuals to screen for microRNAs associated with PFAS exposure. After verification by qPCR, associations between PFAS exposure and expression of 18 selected microRNAs were validated by qPCR in 232 individuals. In silico functional analyses were performed using Ingenuity pathway analysis (IPA).
Three microRNAs were consistently associated with PFAS exposure in the different steps of the study: miR-101-3p, miR-144-3p and miR-19a-3p (all downregulated with increasing exposure). In silico functional analyses suggested that these PFAS-associated microRNAs were annotated to e.g. cardiovascular function and disease, Alzheimer’s disease, growth of cancer cell lines and cancer. Seven predicted target genes for the downregulated microRNAs were annotated to PFAS in IPA knowledge database: DNA methyltransferase 3 alpha (DNMT3a), epidermal growth factor receptor (EGFR), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), nuclear receptor subfamily 1, group H, member 3 (NR1H3), peroxisome proliferator-activated receptor alpha (PPARα), prostaglandin-endoperoxide synthase 2 (PTGS2), and tumour growth factor alpha (TGFα).
PFAS exposure was associated with downregulation of specific microRNAs. Further, in silico functional analyses suggest potential links between the specific PFAS-associated microRNAs, specific microRNA target genes and possibly also health effects.