Determination of Rutin in Cigarette Tobacco, Filters, Mainstream Smoke and Burned Ash of Different Branded Cigarettes by High Performance Liquid Chromatography

Tobacco consists of at least 3,800 chemical constituents. Among them, rutin is an important polyphenolic secondary metabolite in tobacco, which has positive actions such as antiallergic, anti-inflammatory and vasoactive, antitumor, antibacterial, antiviral and anti-protozoal properties. A high performance liquid chromatography method was used to analyze rutin in tobacco and filters, mainstream smoke, and burned ash of ten varieties of cigarettes made in China. The chromatographic analysis was performed on a Hypersil ODS2 column with a gradient elution of acetonitrile and water at a flow rate of 1.0 mL/min. Detection was carried out at 350 nm using a photodiode array detector. The calibration curves for the determination of analytes showed good linearity over the investigated ranges (R2 > 0.9998). Precision and reproducibility were evaluated by six replicated analyses, and the R.S.D. values were less than 0.59% and 1.53%. The recoveries were between 98.47 and 100.84%. Under the optimized conditions, namely 45 mL/g of solvent to solid ratio, 30 min of extraction time and 200 W of ultrasound power, the concentrations of rutin in tobacco and filter, mainstream smoke, burned ash of different brands cigarettes were 10.20–63.98, 0.10–0.32, 0.06–0.16 and 0 μg/per cigarette, respectively

Determination of Rutin in Cigarette Tobacco, Filters, Mainstream Smoke and Burned Ash of Different Branded Cigarettes by High Performance Liquid Chromatography

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Novel Dual-Component Microencapsulated Hydrophobic Amine and Microencapsulated Isocyanate Used for Self-Healing Anti-Corrosion Coating

Dual component microencapsulated hydrophobic amine and microencapsulated isocyanate were designed and fabricated for self-healing anti-corrosion coating. In this system, novel hydrophobic polyaspartic acid ester (PAE) and isophorone diisocyanate (IPDI) were microencapsulated respectively with melamine-formaldehyde (MF) as shell via in situ polymerization. To reduce the reaction activity between shell-forming MF prepolymer and PAE, another self-healing agent tung oil (TO) was dissolved in PAE and subsequently employed as core material. With field-emission scanning electron microscopy (FE-SEM) and optical microscopy (OM), the resultant microencapsulated IPDI with diameter of 2–5 μm showed a spherical shape and smooth surface. More importantly, both the morphology and microstructure of microencapsulated PAE enhanced significantly after addition of TO. Fourier transform infrared spectra (FTIR) analysis confirmed the molecular structure of chemical structure of the microcapsules. Thermal gravimetric analysis (TGA) indicated that both kinds of microcapsules exhibit excellent thermal resistance with the protection of MF shell. Furthermore, the self-healing epoxy coating system containing microencapsulated IPDI and microencapsulated PAE/TO was prepared and investigated. From the micrographs of true color confocal microscope (TCCM), the self-healing coating containing dual-component microcapsules showed excellent self-repairing performance compared to single microencapsulated IPDI system, and the optimal content of dual-component microcapsules in epoxy coating was 20 wt % approximately

A small sample data-driven method: User needs elicitation from online reviews in new product iteration

Eliciting user needs from mass online reviews is playing a significant role in the product iteration process. Efficient user needs elicitation does achieve considerable benefits for maintaining higher competitiveness and a speedier lifecycle. However, there is inevitably an online review scarcity about new products due to the short time on the market and low buyer recognition compared with commonly used products. This paper proposes a small sample data-driven method for user needs elicitation from online reviews in new product iteration. In the first stage, a scraped initial online review dataset is pre-processed roughly to improve the data quality. And then, reviews are classified into multiple categories according to different topics using ERNIE. In the second stage, each topic-based dataset is reprocessed in detail. Thereafter, the key user needs set is determined and facilitated by extracting key product information phrases from every single dataset using improved SIFRank. Moreover, the case study of a smart cat feeder is carried out to demonstrate the feasibility and potential of the ERNIE-ISIFRank methodology. Finally, comparative experiments are conducted to verify the advantages of the proposed method which is primarily based on the pre-trained language model to enhance the deep understanding of the semantics of online reviews. The experimental results confirm that the proposed method can assist in identifying key user needs with high efficiency.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Design Conceptualization and Communicatio

Progesterone attenuates Th17-cell pathogenicity in autoimmune uveitis via Id2/Pim1 axis

Abstract Background Autoimmune uveitis (AU) is the most common ophthalmic autoimmune disease (AD) and is characterized by a complex etiology, high morbidity, and high rate of blindness. AU remission has been observed in pregnant female patients. However, the effects of progesterone (PRG), a critical hormone for reproduction, on the treatment of AU and the regulatory mechanisms remain unclear. Methods To this end, we established experimental autoimmune uveitis (EAU) animal models and constructed a high-dimensional immune atlas of EAU-model mice undergoing PRG treatment to explore the underlying therapeutic mechanisms of PRG using single-cell RNA sequencing. Results We found that PRG ameliorated retinal lesions and inflammatory infiltration in EAU-model mice. Further single-cell analysis indicated that PRG reversed the EAU-induced expression of inflammatory genes (AP-1 family, S100a family, and Cxcr4) and pathological processes related to inflammatory cell migration, activation, and differentiation. Notably, PRG was found to regulate the Th17/Treg imbalance by increasing the reduced regulatory functional mediators of Tregs and diminishing the overactivation of pathological Th17 cells. Moreover, the Id2/Pim1 axis, IL-23/Th17/GM-CSF signaling, and enhanced Th17 pathogenicity during EAU were reversed by PRG treatment, resulting in the alleviation of EAU inflammation and treatment of AD. Conclusions Our study provides a comprehensive single-cell map of the immunomodulatory effects of PRG therapy on EAU and elaborates on the possible therapeutic mechanisms, providing novel insights into its application for treating autoimmune diseases

Preparation carbon nanotube-decorated carbon fibers under low pressure for epoxy-based unidirectional hierarchical composites with enhanced interlaminar shear strength

Multi-walled carbon nanotubes (CNTs) were grown in-situ on the surface of carbon fibers (CFs) at low pressure by a vertical chemical vapor deposition (CVD) reactor. The surface of CFs was modified by electrochemical anodization, and the growth morphology and other properties of CNTs were analyzed by detailed techniques. The CNT-grown CF reinforced unidirectional hierarchical composite material based on the epoxy resin was prepared. The interlaminar shear strength (ILSS) indicates that the maximum strength of the composites reaches 108 MPa after the CNTs are grown on the CF surface with a 25.2% increase than that of the desized CF composites. The fracture surface of composites was observed by scanning electron microscopy (SEM) to further understand the interfacial fracture behavior and enhancement mechanism of CNTs-CF/epoxy composites. The significant improvement in the overall performance of the hierarchical composites can be attributed to the increased adhesion of the interface between the fibers and the resin. The presence of CNTs can restrict the molecular movement of the resin and achieve a strong anchoring interaction, thereby increasing the strength and toughness of the composites and reducing the stress concentration between the layers

16S rRNA gene expression in different <i>Lactobacillus</i> species among condom, IUD and rhythm groups.

<p>Note: Error bars represent the mean ± SE of 16S rRNA gene expression in different <i>Lactobacillus</i> species. Variables were log transformed.</p

Primer sequences and reaction conditions used for PCR of <i>Lactobacillus</i>-specific 16S rRNA gene.

<p>Primer sequences and reaction conditions used for PCR of <i>Lactobacillus</i>-specific 16S rRNA gene.</p

Prevalence rate of H₂O₂-producing <i>Lactobacillus</i> among condom, IUD and rhythm groups.

<p>Note: LB, <i>Lactobacillus</i>; LB⁺, H₂O₂-producing <i>Lactobacillus</i>; LB^-, non-H₂O₂-producing <i>Lactobacillus. P</i>-values were obtained from Chi-square test for comparison of LB⁺ and LB among different groups, including 107/130 in the condom group, 60/88 in the IUD group and 51/75 in the rhythm group. Bonferroni correction was used for pairwise comparison (α = 0.017).</p