bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of quercetin on apoptosis and extracellular matrix degradation of chondrocytes induced by oxidative stress‐mediated pyroptosis
Authors: Wang Qing , Ying Lujing , Wei Bing , Ji Yikui , Xu Yi
Published: November 2021

Quercetin has been preliminarily proven to serve as a potential agent for the treatment of osteoarthritis (OA). However, its effects and potential mechanisms on the pathological process of OA are not very clear. This study aimed to study the protective effect of quercetin on OA. Lipopolysaccharide (LPS)‐treated chondrocytes (C28/I2 cell) and anterior cruciate ligament transection with partial medial meniscectomy‐treated Wistar rats were used as models of OA in vitro and in vivo. Cell counting kit‐8 (CCK‐8 kit), flow cytometry, enzyme‐linked immunosorbent assay (ELISA) kit, western blot, dichlorodihydrofluorescein diacetate (DCFH‐DA) kit, thiobarbituric acid (TBA) test, toluidine blue staining, Hematoxylin eosin (HE) staining and terminal deoxynucleotidyl transferase (TdT)‐mediated dUTP nick‐end labeling (TUNEL) staining were used to evaluate cell viability, cell apoptosis, inflammatory cytokines level, protein expression, reactive oxygen species (ROS) level, malondialdehyde (MDA) content, morphological changes, and chondrocyte apoptosis of cartilage, respectively. Results showed that quercetin could reduce LPS‐induced C28/I2 cell apoptosis, extracellular matrix (ECM) degradation, and cell pyroptosis, and overexpression of nucleotide‐binding domain and leucine‐rich‐repeat‐containing (NLR) family, pyrin domain‐containing 3 (NLRP3) revealed that quercetin reduced chondrocyte apoptosis and ECM degradation by inhibiting NLRP3‐mediated pyroptosis. Furthermore, quercetin could reduce chondrocyte apoptosis and ECM degradation, and inhibit NLRP3‐mediated pyroptosis through blocking oxidative stress. It was further confirmed in the rat OA model that quercetin alleviated OA by blocking oxidative stress, reduces chondrocyte pyroptosis, apoptosis, and ECM degradation. In conclusion, quercetin inhibited OA via blocking oxidative stress‐induced chondrocyte pyroptosis in models of OA in vitro and in vivo.
Christianson syndrome: A novel splicing variant of SLC9A6 causes exon skipping in a Chinese boy and a literature review
Authors: Zhang Xiaoge , Wu Xiaofang , Liu Hongli , Song Tingting , Jiang Yongsheng , He Hanhan , Yang Shaoqing , Xie Yun
Published: November 2021

Background

Variants in the endosomal solute carrier family 9 member A6 (SLC9A6)/(Na+,K+)/H+ exchanger 6 (NHE6) gene have been linked to epilepsy, speech loss, truncal ataxia, hyperkinesia, and postnatal microcephaly.

Methods

In the present study, we evaluated genetic alterations in a 3‐year‐old Chinese boy displayed features of epilepsy, psychomotor retardation, microcephaly, low body weight, difficulty in feeding, excessive movement, attention loss, ataxia, and cerebellar atrophy and his healthy family using WES method. The identified variant was further confirmed by Sanger sequencing method. Finally, minigene assays were used to verify whether the novel SLC9A6 intronic variant influenced the normal splicing of mRNA.

Results

We identified a novel hemizygous splicing variant [NM_001042537.1: c.1463‐1G>A] in SLC9A6 by trio‐based exome sequencing. The minigene expression in vitro confirmed the splicing variant altered a consensus splice acceptor site of SLC9A6 intron 11, resulting in skipping over exon 12.

Conclusions

Our finding extends the catalog of pathogenic intronic variants affecting SLC9A6 pre‐mRNA splicing and provides a basis for the genetic diagnosis of CS.
Successful endoscopic cyanoacrylate injection therapy for ruptured duodenal varices immediately after balloon‐occluded retrograde transvenous obliteration
Authors: Tamai Yasuyuki , Tanaka Hideaki , Fujimori Masashi , Iwasa Motoh , Nakagawa Hayato
Published: November 2021

We present a rare case of acute duodenal variceal rupture after B‐RTO that was successfully treated with endoscopic CA injection therapy. A 74‐year‐old Japanese woman was transferred to our hospital due to progressive general malaise and hematemesis. Gastroduodenoscopy (GDS) showed duodenal varices without active bleeding in the second portion of duodenum. Balloon‐occluded retrograde transvenous obliteration (B‐RTO) was carried out to prevent duodenal variceal rebleeding. Good pooling of ethanolamine oleate with iopamidol (EOI) was observed in duodenal varices using balloon catheters. However, massive melena was observed immediately after B‐RTO. Emergent GDS revealed a white plug on the treated varix, thus endoscopic cyanoacrylate (CA) injection therapy was performed. We speculated that the injection of EOI increased the pressure in the duodenal varices which resulted in rupture of duodenal varices. B‐RTO was effective therapy to prevent duodenal variceal rebleeding, but postprocedural monitoring is required as illustrated by this case. We suggest that careful monitoring and backup system for endoscopy are required during or after B‐RTO.
One‐pot three‐component synthesis of novel chromeno[3,2‐c]pyridine‐1,9(2H)‐diones by using SnCl2⋅2H2O as catalyst
Authors: Kamali Mahmood , Keramat Pirolghor Fatemeh
Published: November 2021

An efficient method was developed to prepare a novel series of chromeno[3,2‐c]pyridine‐1,9(2H)‐diones from bio‐based 4‐hydroxy‐6‐methylpyridine‐2‐ones, aromatic aldehydes and dimedone in the presence of SnCl2⋅2H2O in ethanol at 70°C. Mild conditions as well as the operational simplicity, easy workup, and environmentally friendly are the most advantages of this multicomponent synthesis of potentially bioactive new products.
Regioselective alkylation reaction of purines under microwave irradiation
Authors: Vinuesa Arturo , Viñas Miquel , Jahani Daniel , Ginard Jaume , Mur Nuria , Pujol Maria Dolors
Published: November 2021

The alkylation of purines which is generally carried out after anion formation by treatment with a base and alkyl halide is complicated and in the best cases, mixtures of N‐alkylated compounds are obtained. Purine derivatives can be acquired from alkylation at N‐7 and N‐9. In this work, the reaction conditions have been optimized to obtain the alkylation products of N‐9 regioselectively. Different bases have been tried and tetrabutylammonium hydroxide has led to the best results. The reaction depends on the type of base and solvent used and improves considerably when the aid of microwave irradiation is used, which also considerably reduces the reaction time by reducing the formation of secondary products.
Non‐Invasive Assessment of Damping of Blood Flow Velocity Pulsatility in Cerebral Arteries With MRI
Authors: Arts Tine , Onkenhout Laurien P. , Amier Raquel P. , van der Geest Rob , van Harten Thijs , Kappelle Jaap , Kuipers Sanne , van Osch Matthijs J.P. , van Bavel Ed T. , Biessels Geert Jan , Zwanenburg Jaco J.M. ,   Heart‐Brain Connection Consortium
Published: November 2021

Background

Damping of heartbeat‐induced pressure pulsations occurs in large arteries such as the aorta and extends to the small arteries and microcirculation. Since recently, 7 T MRI enables investigation of damping in the small cerebral arteries.

Purpose

To investigate flow pulsatility damping between the first segment of the middle cerebral artery (M1) and the small perforating arteries using magnetic resonance imaging.

Study Type

Retrospective.

Subjects

Thirty‐eight participants (45% female) aged above 50 without history of heart failure, carotid occlusive disease, or cognitive impairment.

Field Strength/Sequence

3 T gradient echo (GE) T1‐weighted images, spin‐echo fluid‐attenuated inversion recovery images, GE two‐dimensional (2D) phase‐contrast, and GE cine steady‐state free precession images were acquired. At 7 T, T1‐weighted images, GE quantitative‐flow, and GE 2D phase‐contrast images were acquired.

Assessment

Velocity pulsatilities of the M1 and perforating arteries in the basal ganglia (BG) and semi‐oval center (CSO) were measured. We used the damping index between the M1 and perforating arteries as a damping indicator (velocity pulsatilityM1/velocity pulsatilityCSO/BG). Left ventricular stroke volume (LVSV), mean arterial pressure (MAP), pulse pressure (PP), and aortic pulse wave velocity (PWV) were correlated with velocity pulsatility in the M1 and in perforating arteries, and with the damping index of the CSO and BG.

Statistical Tests

Correlations of LVSV, MAP, PP, and PWV with velocity pulsatility in the M1 and small perforating arteries, and correlations with the damping indices were evaluated with linear regression analyses.

Results

PP and PWV were significantly positively correlated to M1 velocity pulsatility. PWV was significantly negatively correlated to CSO velocity pulsatility, and PP was unrelated to CSO velocity pulsatility (P = 0.28). PP and PWV were uncorrelated to BG velocity pulsatility (P = 0.25; P = 0.68). PWV and PP were significantly positively correlated with the CSO damping index.

Data Conclusion

Our study demonstrated a dynamic damping of velocity pulsatility between the M1 and small cerebral perforating arteries in relation to proximal stress.

Level of Evidence

4

Technical Efficacy

Stage 1
Early feeding after percutaneous endoscopic gastrostomy tube placement in patients who require trauma and surgical intensive care: A retrospective cohort study
Authors: Shahmanyan Davit , Lawrence Jeffrey C. , Lollar Daniel I. , Hamill Mark E. , Faulks Emily R. , Collier Bryan R. , Chestovich Paul J. , Bower Katie L.
Published: November 2021

Background

Critically ill patients experience interruptions in enteral nutrition (EN). For ventilated patients who undergo percutaneous endoscopic gastrostomy (PEG) tube placement, postprocedure fasting times vary from 1 to 24 h depending on the surgeon's preference. There is no evidence to support delayed feeding (DF) after PEG placement. This study's purpose was to determine if there is an increased complication rate associated with early feeding (EF) after PEG.

Methods

150 adult ventilated patients in the trauma and surgical intensive care unit (TSICU) at a level I trauma center underwent PEG placement in March 2015 through May 2018 by one of six surgical intensivists. Retrospective review revealed variable post‐PEG fasting practices: one started EN at 1 h, two started at 4 h, two started at 6 h, and one started at 24 h. Time to initiation of EN and complication rates were assessed. Patients were divided into EF (<4) and DF (≥4 h) groups.

Results

Median postprocedure fasting time was 5.5 h. The overall complication rate was 3.3%, with a feeding intolerance rate of 0.7% and aspiration rate of 0%. There was no difference in complication rate for EF (3.1%) as compared with DF (3.4%) (odds ratio, 0.92; 95% CI, 0.10–8.52; P = 0.7).

Conclusion

Complication rates following PEG placement in ventilated TSICU patients are low and do not change with EF compared with DF. EF is probably safe.
LncPVT1 regulates osteogenic differentiation of human periodontal ligament cells via miR‐10a‐5p/brain‐derived neurotrophic factor
Authors: Li Xiaobei , Huang Yiping , Han Yineng , Yang Qiaolin , Zheng Yunfei , Li Weiran
Published: November 2021

Background

Identifying the factors affecting osteoblast differentiation of periodontal ligament cells (PDLCs) can help enhance the regeneration of periodontal tissue. LncRNA plasmacytoma variant translocation 1 (lncPVT1) is an important regulatory factor involved in many biological processes, but its role in osteogenesis remains unclear.

Methods

Expressions of osteogenic markers were detected by quantitative reverse transcription polymerase chain reaction and Western blot analysis. Alkaline phosphatase staining was conducted for early osteoblast differentiation and alizarin red S staining was used for mineral deposition. RNA sequencing was used to identify the miRNAs regulated by lncPVT1 during osteogenesis. Cell transfection was used to overexpress or knockdown lncPVT1 and miR‐10a‐5p. Dual luciferase reporter assays were conducted to analyze the binding of miR‐10a‐5p to brain‐derived neurotrophic factor (BDNF).

Results

LncPVT1 was significantly increased during osteogenic induction of PDLCs. Overexpression of lncPVT1 promoted osteogenesis, whereas lncPVT1 knockdown inhibited this process. RNA sequencing showed that miR‐10a‐5p expression was significantly increased after lncPVT1 knockdown. RNA immunoprecipitation assay further demonstrated the binding potential of lncPVT1 and miR‐10a‐5p. MiR‐10a‐5p inhibited the osteogenesis of PDLCs, and partially reversed the stimulatory effects of lncPVT1. Subsequently, we identified a predicted binding site for miR‐10a‐5p on BDNF and confirmed it using dual luciferase reporter assays. Moreover, lncPVT1 upregulated the expression of BDNF, whereas miR‐10a‐5p downregulated BDNF expression. BDNF promoted osteogenesis and partially rescued the si‐lncPVT1‐mediated inhibition of PDLCs osteogenic differentiation.

Conclusions

LncPVT1 positively regulated the osteogenic differentiation of PDLCs via miR‐10a‐5p and BDNF. Our results provide a promising target for enhancing the osteogenic potential of PDLCs.
Changes in protease activity during fermentation of fish sauce and their correlation with antioxidant activity
Authors: Bu Ying , Liu Yingnan , Luan Hongwei , Zhu Wenhui , Li Xuepeng , Li Jianrong
Published: November 2021

BACKGROUND

Antioxidant activity has been found in fermented fish sauce. In this experiment, the properties of endogenous protease and antioxidant activity were studied in anchovy sauce during fermentation. The correlation between protease activity and antioxidant activity in fermented anchovy sauce was analyzed using the partial least squares (PLS) method.

RESULTS

The results showed that at least four proteases were present in the endogenous enzyme solution, and the optimum pH values were 2.5, 5.5, 9.0, and 12.5, respectively. The maximum inhibition rate of endogenous protease, from high to low, was: serine protease inhibitor > trypsin inhibitor > aspartic protease inhibitor (pepsin inhibitor) > cysteine protease inhibitor > metalloprotease inhibitor. At the sixth month of fermentation, fish sauce had stronger trypsin, pepsin‐like activity, and antioxidant activity. At the ninth month of fermentation, the cathepsin activity was greater. A model correlating changes in protease activity with antioxidant activity suggested that the trypsin and serine protease were the main factors affecting antioxidant activity.

CONCLUSION

This study reports a model correlating changes in protease activity with the antioxidant activity of fish sauce. It lays a foundation for further exploration of the formation of antioxidant substances and antioxidant effects during the process of fish sauce fermentation. © 2021 Society of Chemical Industry.
A pseudotargeted method based on sequential window acquisition of all theoretical spectra mass spectrometry acquisition and its application in quality assessment of traditional Chinese medicine preparation‐Yuanhu Zhitong tablet
Authors: Li Lele , Wang Yang , Li Yuxuan , Zhu Heyun , Feng Bo
Published: November 2021

Quality control plays a key role in the application of Chinese materia medica, especially in the preparation of traditional Chinese medicine. A pseudotargeted analysis method using an ultra‐high‐performance liquid chromatography‐quadrupole‐time‐of‐flight‐mass spectrometry that was operated in the sequential window acquisition of all theoretical spectra mode was proposed to explore the chemical markers of traditional Chinese medicine preparation. Full‐scan‐based untargeted analysis was applied to extract the target ions. After data preprocessing, 302 target ions were extracted and used for the subsequent sequential window acquisition of all theoretical spectra analyses. The established sequential window acquisition of all theoretical spectra‐based pseudotargeted approaches exhibited good repeatability and a wide linear range. The established method was successfully applied to discover analytical markers for the Yuanhu Zhitong tablet. After multivariate statistical analysis, 94 potential markers were identified. Ten markers were annotated by matching accurate m/z and product ion information obtained from previous reports. It is clearly indicated that the pseudotargeted analysis could make a great contribution to the quality assessment of traditional Chinese medicine preparation as a newly emerging technique.
Temperature‐dependent evolution of cell morphology and carbon and nutrient content in a marine diatom
Authors: O'Donnell Daniel R. , Beery Sophia M. , Litchman Elena
Published: November 2021

Phytoplankton are key players in global biogeochemical cycles, and the effects of ocean warming on their carbon–nitrogen–phosphorus (CNP) stoichiometry, photosynthesis, size, morphology, growth rates, and other traits are of great ecological consequence. The physiological mechanisms of adaptation to temperature in phytoplankton are poorly understood, as are the consequences of the evolution of these processes (e.g., nutrient uptake, photosynthesis) for global biogeochemistry. In general, high temperatures favor smaller cells with higher surface area‐to‐volume ratios, but repeatable patterns in cellular CNP stoichiometry across temperature remain elusive. Here, we compared thermal reaction norms for cellular C, N, P, and chlorophyll a (Chl a) content and for carbon assimilation rate in replicate populations of the marine diatom Thalassiosira pseudonana evolved for 500 generations at 16°C and 31°C. We also examined the thermal reaction norms for cell volume and morphological traits. T. pseudonana has a cylindrical frustule and likely primarily exchanges materials with the environment through the round valve faces. We found that the 31°C‐selected T. pseudonana populations had smaller cells and higher per‐biovolume densities of nutrients and Chl a than the 16°C‐selected populations across assay temperatures but there were no detectable patterns in CNP stoichiometry. The 31°C‐selected populations also had higher valve surface area‐to‐cell volume ratio that increased more with temperature, suggesting better nutrient uptake capabilities than in the 16°C‐selected populations. Our study demonstrates that temperature‐dependent physiological plasticity may evolve differently at different temperatures and suggests that future phytoplankton communities will consist of smaller, more nutrient‐dense cells.
Investigation of Self‐Assembly of Symmetric and Asymmetric Peptide Bolaamphiphiles by COSMO‐RS and Atomistic Simulations and Their Interactions with POPC Bilayers
Authors: Lebedenko Charlotta G. , Banerjee Ipsita A.
Published: November 2021

In this work, eight new peptide bolaamphiphiles (PbAs) are designed containing polar (serine or threonine) and nonpolar amino acid head groups (tryptophan or tyrosine) connected by varying aliphatic carbon chains of different lengths and saturation. The physicochemical properties of the bolaamphiphiles are examined by COSMO‐RS to determine sigma profiles, potential, and sigma surfaces. Self‐assembly is studied using atomistic molecular dynamic simulations under protonated and deprotonated conditions. To mimic physiological conditions, simulations are also carried out in the presence of sodium chloride and the impact of salt on the self‐assembly process is also studied. In general, hydrophobic PbAs are found to form higher‐order supramolecular structures while PbAs connected by shorter chains or hydrophilic head groups form globular, more compact structures. Self‐assembly is more favorable when the PbAs are protonated. Membrane interactions are then studied using MD simulations and the results indicate that the hydrophobic PbAs interact more favorably with the POPC membrane surfaces. These simulations provide insights about the intricate interactions and properties of the PbAs and shed light on the ability to form fine‐tuned structures at the nanoscale. This study may lead to the development of novel PbAs for potential applications in a wide variety of biological applications.
Analytical solutions describing the oblique flow of a viscous incompressible fluid around a dendritic crystal
Authors: Alexandrov Dmitri V. , Galenko Peter K.
Published: November 2021

This article considers the hydrodynamic problem of an oblique flow of a viscous incompressible fluid around the tip of a dendritic crystal. Approximate analytical solutions of Oseen's hydrodynamic equations are obtained in 2D and 3D cases using special curvilinear coordinates. It is shown that the projections of the fluid velocity change significantly with a change in the flow slope and Reynolds number. The theory developed in this work has a limiting transition to the previously known solutions for the rectilinear (without tilt) fluid flow around a dendrite.
Development of a Food Composition Database for Assessing Nitrate and Nitrite Intake from Animal‐based Foods
Authors: Zhong Liezhou , Liu Alex H. , Blekkenhorst Lauren C. , Bondonno Nicola P. , Sim Marc , Woodman Richard J. , Croft Kevin D. , Lewis Joshua R. , Hodgson Jonathan M. , Bondonno Catherine P.
Published: November 2021

Scope

Nitrate and nitrite are approved food additives in some animal‐based food products. However, nitrate and nitrite in foods are strictly regulated due to health concerns over methaemoglobinaemia and the potential formation of carcinogenic nitrosamines. In contrast, plants (like leafy vegetables) naturally accumulate nitrate ions; a growing body of research reveals beneficial metabolic effects of nitrate via its endogenous conversion to nitric oxide. To refine the association of dietary nitrate and nitrite intake with health outcomes, reliable measures of nitrate and nitrite intake from dietary food records are required. While a vegetable nitrate content database has been developed, there is a need for a comprehensive up‐to‐date nitrate and nitrite content database of animal‐based foods.

Methods and Results

A systematic literature search (1980–September 2020) on the nitrate and nitrite content of animal‐based foods is carried out. Nitrate and nitrite concentration data and other relevant information are extracted and compiled into a database. The database contains 1921 entries for nitrate and 2077 for nitrite, extracted from 193 publications. The highest median nitrate content is observed in chorizo (median [IQR]; 101.61 [60.05–105.93] mg kg‐1). Canned fish products have the highest median nitrite level (median [IQR]; 20.32 [6.16–30.16] mg kg‐1). By subgroup, the median nitrate value in industrial processed meat products (e.g., uncured burger, patties and sausages), whole milk powder and in particular red meat are higher than cured meat products. Processed meat products from high‐income regions have lower median nitrate and nitrite content than those of middle‐income regions.

Conclusion

This database can now be used to investigate the associations between nitrate and nitrite dietary intake and health outcomes in clinical trials and observational studies.
An efficient computational approach for three‐dimensional modeling and simulation of fibrous battery electrodes
Authors: Goudarzi Mohsen , Grazioli Davide , Simone Angelo
Published: November 2021

Fibrous electrodes are a promising alternative to conventional particle‐based lithium‐ion battery electrodes. In this contribution, we propose an efficient computational approach for the modeling and simulation of electrochemical phenomena taking place in fibrous electrodes during battery charge/discharge processes. Since each fiber is explicitly modeled by means of a dimensionally reduced embedded fiber model, the framework enables simulations in a three‐dimensional setting with relatively modest discretization and computational requirements compared to simulations with fully resolved fiber discretizations. The approach is applied to electrodes with high volume fractions of high aspect ratio fibers. Various local and global quantities are analyzed and results are compared to those obtained with the standard finite element method and the pseudo‐2D model.
Protonated Ethylene Carbonate: A Highly Resonance‐Stabilized Cation
Authors: Beck Stefanie , Jessen Christoph , Kornath Andreas J.
Published: November 2021

Salts containing the monoprotonated ethylene carbonate species of were obtained by reacting it with the superacidic systems XF/MF5 (X=H, D; M=Sb, As). The salts in terms of [C3H5O3]+[SbF6]−, [C3H5O3]+[AsF6]− and [C3H4DO3]+[AsF6]− were characterized by low‐temperature infrared and Raman spectroscopy. In order to generate the diprotonated species of ethylene carbonate, an excess of Lewis acid was used. However, this only led to the formation of [C3H5O3]+[Sb2F11]−, which was characterized by a single‐crystal X‐ray structure analysis. Quantum chemical calculations on the B3LYP/aug‐cc‐PVTZ level of theory were carried out for the [C3H5O3]+ cation and the results were compared with the experimental data. A Natural Bond Orbital (NBO) analysis revealed sp2 hybridization of each atom belonging to the CO3 moiety, thus containing a remarkably delocalized 6π‐electron system. The delocalization is confirmed by a 13C NMR‐spectroscopic study of [C3H5O3]+[SbF6]−.
The effects of public governance and national culture on money laundering: A structured equation modeling approach
Authors: AlQudah Anas , Bani‐Mustafa Ahmed , Nimer Khalil , Alqudah Abdullah D. , AboElsoud Mostafa E.
Published: November 2021

In this study, we investigate the role of public governance in mediating the impact of a country's culture on money laundering. We assess whether interference in the form of public governance can reduce or offset cultural effects with respect to the risks associated with money laundering across 92 countries over a 6‐year period (2012–2017).

Design/methodology/approach

This research uses structural modeling to examine the direct path between culture and money laundering, and the indirect path between culture and money laundering that passes through public governance as a mediator. We use Hofstede's cultural variables as a proxy for measuring culture, and Worldwide Governance Indicators (WGIs) to measure public governance in different countries. The Basel anti‐money laundering index is also used as a proxy for measuring money laundering risk.

Findings

Our results show that public governance fully mediates the relationship between culture and money laundering. The direct path shows a significant relationship between culture and money laundering, but this relationship becomes insignificant when public governance is introduced as a mediator.

Originality/value

This study indicates that governments can reduce money‐laundering risk by paying more attention to the quality of public governance and its potential as a tool in reducing money laundering.
A novel Pinus roxburghii natural leaves fiber used as reinforcement polymer composite: As asbestos‐free brake friction material
Authors: Kumar Naresh , Grewal Jasmaninder Singh , Kumar Nitin , Kumar Sushil , Ali Sarafat
Published: November 2021

Nowadays, industries are increasing the use of natural fiber in many applications due to its cheap, eco‐friendly, and better mechanical properties. Asbestos and Kevlar, which are the most popular material, have been proven toxic and harmful to the environment and the human body. It has been proven that asbestos causes cancer, mesothelioma, and affects the respiratory system of humans. Moreover, the most trending material Kevlar is also showing the same effects. So, it is necessary to find out a substitute for asbestos and Kevlar. In this direction, a novel Pinus roxburghii leaves fiber is used as a friction material to develop new brake pad materials in the hind‐type brake molding machine. The composition of Pinus roxburghii leaves fiber was taken 5%–20% in the polymer brake pad composites. All the practical work has been done in the brake pad company (Allied Nippon Ghaziabad). As a result, 5% composition has shown good mechanical, physical, chemical, tribological, and thermal results, while thermal stability and recovery was found highest for 20% composition. The shear strength, tensile strength, proof strength, and impact energy have shown good results for the 10% composition of Pinus roxburghii leaves fiber in polymer composite.
Evaluation of monomer elution, microhardness, and roughness of experimental dental composite resins prepared from Bis‐EFMA, a novel monomer system
Authors: Hatipoğlu Ömer , Turumtay Emine Akyüz , Saygın Ayşegül Göze
Published: November 2021

This study aimed to compare the monomer elution, microhardness, and roughness of experimental resin‐based composites (RBCs) prepared from a novel monomer system derived from 9,9‐Bis[4‐(2‐hydroxyethoxy)phenyl]fluorene) (Bis‐EFMA), bisphenol A‐glycidyl methacrylate (Bis‐GMA), and urethane dimethacrylate (UDMA) with each other, also with a commercial RBC, 3 M ESPE FiltekTM Z250 (FZ). Experimental Bis‐EFMA (ET), Bis‐GMA (BT), and UDMA (UT) based composites were prepared (20% Bis‐EFMA or 20% Bis‐GMA or 20% UDMA, and 20% triethylene glycol dimethacrylate [TEGDMA], and 60% glass filler). 60 specimens were produced (n = 5) and exposed to ethanol solution for 7 days. Then specimens were tested at baseline (T0), first (T1), third (T2), and seventh (T3) days. ET and FZ released significantly lower TEGDMA than other RBCs did (p < 0.05). BT released significantly higher TEGDMA than other RBCs did at T1 (p < 0.05). However, no significant difference was found between FZ and ET at T1 (p > 0.05). FZ exhibited the highest microhardness at all‐time points; besides, the microhardness of BT was lowest at T0, while the microhardness of BT and UT was lower than that of FZ and ET at T1, T2, and T3 (p < 0.05). BT exhibited higher roughness at T2 than the UT did at T0 and T1, significantly (p < 0.05). However, no significant difference was found between the other RBCs (p > 0.05). Bis‐EFMA, a novel bisphenol A‐free monomer system, has the potential to be used in commercial RBCs as a substitute for Bis‐GMA in terms of lower monomer elution and higher microhardness.
Toughening of epoxy by nanostructures with ABA triblock copolymers: An influence of organosilicon modification of block copolymer
Authors: Li Lei , Peng Wenjun , Liu Liyue , Zheng Sixun
Published: November 2021

In this work, we investigated the effect of organosilicon modification of an ABA triblock copolymer on the morphologies, thermal properties, and fracture toughness of epoxy thermosets. First, a poly(ε‐caprolactone)‐block‐poly(butadiene) ‐block‐poly(ε‐caprolactone) triblock copolymer was synthesized through the ring‐opening polymerization of ε‐caprolactone by using an α,ω‐dihydroxyl‐terminated polybutadiene as the macromolecular initiator. Thereafter, the triblock was organosilicon‐modified via the hydrosilylation of its midblock (viz. polybutadiene) with pentamethyldisiloxane. It was found that the organosilicon modification resulted in a switch of the nanostructure formation mechanism from reaction‐induced microphase separation to self‐assembly. As a consequence of the organosilicon modification, the morphological structures of the thermoset were significantly changed, and thus, the materials displayed different improvement in fracture toughness. In addition, the organosilicon modification further enhanced the surface hydrophobicity of the materials.
Bilobalide molecularly imprinted polymers prepared using MWCNTs/ZIF‐67 composite as supporter for solid‐phase extraction of bilobalide from real samples
Authors: Huang Xusheng , Liu Qingsong , Zhang Wencheng , Wu Zeyu , Wang Yunchun , Li Jianwen , Xiong Baoyi , Xian Zhaojun
Published: November 2021

The preparation of raw materials is an important prerequisite for studying the function of natural active ingredients. Here, the preparation of MWCNTs/ZIF‐67@MIPs based on surface molecular imprinting technology for the separation of bilobalide (BB) from real samples was proposed. The successful preparation of MWCNTs/ZIF‐67@MIPs was demonstrated using several techniques. Adsorption equilibrium was achieved when the time was 4 h, and the rate of adsorption calculated from the dynamic adsorption results was 14.2 μg mL–1 h–1. The maximum adsorption amount for MWCNTs/ZIF‐67@MIPs of BB was calculated to be 59.2 mg g–1, which was more than three times that for MWCNTs/ZIF‐67@NIPs (23.1 mg g–1), and the Freundlich isotherm model and pseudo‐second‐order kinetic model were more suitable for the explanation of isothermal and kinetic adsorption behaviors, respectively. The results of selective adsorption indicated that MWCNTs/ZIF‐67@MIPs show excellent selectivity and specificity for BB compared to structurally similar compounds such as ginkgolides A, B and C, with an excellent imprinting factor (2.83). The results of reuse studies indicated that MWCNTs/ZIF‐67@MIPs exhibited great reproducibility with a recovery rate of 70.8% after repeated use for five times. Finally, the developed MWCNTs/ZIF‐67@MIPs were used as a solid‐phase extraction sorbent to directly separate BB from treated gingko leaf extract and crude extract of BB, and the results suggested that the purity of BB in the two samples was increased by about 30%, and the recoveries reached 68.34% and 71.54%, respectively. Meanwhile, the separation effect of MWCNTs/ZIF‐67@MIPs on BB was better than that of BBMIP prepared by bulk polymerization. © 2021 Society of Industrial Chemistry.
Adaptive tracking control for stochastic nonlinear systems with unknown virtual control coefficients
Authors: Zhao Yajing , Liu Cungen , Liu Xiaoping , Wang Huanqing , Zhou Yucheng
Published: November 2021

This article studies the adaptive tracking control problem for stochastic nonlinear systems with unknown virtual control coefficients (UVCCs) being functions of system states. Without using the Nussbaum gain technique (NGT), a new method is introduced to deal with UVCCs. The novel adaptive laws are constructed to compensate parameter uncertainties and UVCCs. Using backstepping method, an adaptive controller is designed, which can ensure that the boundedness in probability of all the signals in the closed‐loop system. In the end, a numerical simulation example and a practical example are given to validate the effectiveness and superiority of the proposed controller.
Containment control of hybrid multi‐agent systems
Authors: Chen Yarui , Zhao Qi , Zheng Yuanshi , Zhu Yunru
Published: November 2021

In this article, the containment control problem is studied for hybrid multi‐agent systems (MASs), which is comprised of continuous‐time and discrete‐time dynamic agents. For first‐order hybrid MASs, two effective distributed protocols are designed when followers have continuous‐time dynamics, and one distributed protocol is designed when followers have discrete‐time dynamics. Meanwhile, for second‐order hybrid MASs, we also propose three kinds of distributed protocols to solve the containment control. By utilizing stability theory and system transformation method, some criteria are derived for solving the containment control problem of hybrid MASs. Simulation examples are provided to show the efficiency of the theoretical results.
Dynamic event‐based recursive filtering for multirate systems with integral measurements over sensor networks
Authors: Shen Yuxuan , Wang Zidong , Dong Hongli , Alsaadi Fuad E. , Liu Hongjian
Published: November 2021

In this paper, the dynamic event‐based recursive filtering problem is studied for multirate systems over sensor networks. The state update rate of the plant and the sampling rate of the sensors are allowed to be different in order to reflect the multirate sampling strategy. Moreover, the phenomenon of integral measurements is considered to cater for the real engineering practice. To reduce unnecessary data transmissions, the dynamic event‐based mechanism is implemented in the communication channels among sensor nodes. The purpose of this paper is to design a distributed recursive filtering scheme such that, under the influence of the integral measurements, the multi‐rate sampling, and the dynamic event‐based mechanism, there exists a minimal upper bound on the filtering error covariance. An upper bound on the filtering error covariance is first derived by solving a matrix Riccati equation, and then minimized at each sampling instant by choosing appropriate filter gains. Comprehensive simulations are conducted on a numerical example and a practical example to show the effectiveness and superiority of the proposed dynamic event‐based recursive filtering scheme.
Linking litter decomposition to soil physicochemical properties, gas transport, and land use
Authors: Fu Yuting , de Jonge Lis W. , Greve Mogens H. , Arthur Emmanuel , Moldrup Per , Norgaard Trine , Paradelo Marcos
Published: November 2021

Litter decomposition is a critical process in carbon cycling, which can be affected by land use. The relationship between litter decomposition and soil properties under different land uses remains unclear. Litter decomposition can be quantified by the Tea Bag Index (TBI), which includes a decomposition ratekand a stabilization factorS. Our objective was to investigate linkages between TBI and soil physicochemical and gas transport properties and land use. We buried three pairs of tea bags in 20 sites (covering cropland, grassland, heathland, and forest land uses) in a transect from the western to the eastern coast of the Jutland peninsula, Denmark. The tea bags were retrieved after 90 d and TBI was determined. Disturbed and undisturbed (100 cm3soil cores) samples were collected from each site. Thereafter, clay content, organic carbon (OC), bulk density (ρb), pH, electrical conductivity (EC), oxalate‐extractable phosphorus (Pox), aluminum (Alox), and iron (Feox) content, soil water content, gas diffusivity (Dp/D0), and air permeability (ka) at −10 kPa were measured. Results showed that grasslands had the highestkandSamong four land uses, and agricultural soils (croplands and grasslands) exhibited higher TBI values than seminatural soils (forest and heathland). The prediction ofSwas better than that ofkbased on multiple linear regression analysis involving soil physicochemical properties. Clay content and OC were not strong predictors. IncludingDp/D0andkaimproved the prediction ofS, and finally, the inclusion of land use enhanced the prediction of bothkandS. The different trends between two distinct land‐use groups can be attributed to pH, Pox, and ρb.
A Facile Approach for the Synthesis of SrTiO3/g‐C3N4 Photo‐catalyst and its Efficacy in Biodiesel Production
Authors: Ghani Naila , Iqbal Javed , Sadaf Sana , Bhatti Haq Nawaz , Asgher Muhammad
Published: November 2021

Visible light active photocatalysts have attracted a lot of interest due to their simple chemical workup and recyclability. In this study, the role of Strontium Titanate/graphitic Carbon Nitride composite (SrTiO3/g‐C3N4) was investigated for the pretreatment of waste frying oil (WFO) to reduce high free fatty acids (FFAs) for biodiesel production. SrTiO3/g‐C3N4 photo‐catalyst was synthesized through the facile refluxing method and its activity was also compared with simple graphitic carbon nitride (g‐C3N4). Experimental results revealed that SrTiO3/g‐C3N4 possesses higher efficiency as compared to g‐C3N4. Photo‐catalyst was characterized through SEM‐EDX, XRD and FT‐IR. Maximum conversion of FFAs (85 %) was achieved at 1 % catalyst dose, 800 rpm stirring speed, 3 : 1 methanol to oil ratio, and 4 hours of reaction time. Esterified WFO was converted to waste frying oil methyl esters (WFOME) by using CaO‐KOH heterogeneous catalyst. The maximum yield of WFOME was obtained at 1.25 % catalyst dose, 65 °C, 600 rpm, 2 h of reaction time, and 12 : 1 methanol to oil ratio. Physicochemical analysis of WFOME revealed that it is in accord with ASTM standards.
Anti‐proliferative Activities of Thiophenes, Pyrans and PyridinesDerived from 1,3‐Dicarbonyl Compounds
Authors: Alahmdi Mohammed I. , Mohareb Rafat Milad , Abdelaziz Mahmoud Mahmoud A. , Alkhamis Kholood , Abo‐Dya Nader Elmaghwry , Zidan Nahla S. , Khasim Syed , Alsharif Meshari A.
Published: November 2021

In the present work, the reaction of the acetoactanilide derivatives with either benzenediazonium chloride, 4‐chlorobenzenediazonium chloride, or 4‐methoxybenzenediazonium, gave arylhydrazone derivatives. Heterocyclizations of the latter compounds were carried out to afford new thiophene, pyran and pyridine derivatives. The cyctotoxicity of the synthesized compounds against the selected six cancer cell lines was determined where eleven compounds exhibited the highest inhibitions. Through out this work, the produced pyridazine derivatives were selected for evaluation against cancer cell lines categorized according to the disease and the compounds showed high inhibitions. The results obtained in this work encourage further work in the future.
Pyrenyl‐Based Aggregation‐Induced Emission Luminogen for Highly Sensitive and Selective Detection of 2,4,6‐Trinitrotoluene in Water
Authors: Hao Hongmin , Ye Zijian , Dai Hui , Liu Cong , Yi Aihua , Xu Bingjia , Shi Guang , Su Shichen , Azad Fahad , Chi Zhenguo
Published: November 2021

Trace detection of nitroaromatic explosives in aqueous solution is important for environmental pollution evaluation and terrorist prevention. Here, a new pyrenyl‐based aggregation‐induced emission (AIE) fluorochrome (CPPyV) with desirable fluorescent performance was synthesized and applied to detect 2,4,6‐trinitrotoluene (TNT) in water. The fluorescence of CPPyV can be selectivity and efficiently quenched by TNT. The Stern‐Volmer constant (KSV) of CPPyV for TNT was determined to be 6.2×105 M−1, with a low detection limit of 4 nM. Notably, CPPyV could be used for TNT determinations in real water samples and also developed as a fluorescent paper sensor which could efficiently detect TNT by naked‐eye when the TNT concentration was 1.0×10−8 M. The quenching process was dynamic quenching mechanism and the theoretical calculations revealed that photoin‐duced electron transfer (PET) from excited CPPyV to electron deficient TNT was the main reason for fluorescence quenching. The excellent detection performance of CPPyV yielded it a promising sensor material for actual field applications.
Molecular Recognition of Biologically Relevant Anions with an Expanded Dinuclear Copper(II) Complex: An Efficient Sensor for Oxalate Anion in Aqueous Solution
Authors: Rhaman Md Mhahabubur , Owens Harold , Powell Douglas R. , Hossain Md. Alamgir
Published: November 2021

An expanded dinuclear copper(II) complex (1) derived from a biphenyl‐based hexaazamacrocyle (L) was synthesized and characterized by single crystal X‐ray analysis, exhibiting a boat‐shaped cavity with an elongated CuII⋅⋅⋅CuII distance of 11.01 Å. The dinuclear copper(II) complex was investigated for a verity of biologically relevant anions including carboxylates (oxalate, citrate, tartrate, glutamate, adipate, acetate and benzoate), oxoanions (phosphate, sulphate, perchlorate and nitrate), and halides (fluoride, chloride, bromide and iodide) by competitive fluorescence titrations via indicator displacement assay (IDA) using an external dye (Eosin Y) in water‐methanol solution at neutral pH. The receptor was shown to exhibit strong affinity for oxalate, providing the binding trend: oxalate (log K=6.07)>citrate (log K=5.74)>phosphate (log K=5.02)>tartrate (log K=4.78)>glutamate (log K=4.42)>adipate (log K=4.31)>acetate (log K=4.14)>benzoate (log K=4.01). No interaction was observed for other anions including sulphate, perchlorate, nitrate, fluoride, chloride, bromide and iodide under the identical conditions.
Biosynthesized Nanosilver from Alginate Dialdehyde: An In Vitro Evaluation
Authors: Resmi Rajalekshmi , Parvathy Jayasree , Saravana Ramakrishna Perumal , Raj Gijo , Joseph Roy
Published: November 2021

The superior antimicrobial properties of nanosilver (AgNP) led to its applications in healthcare and hygiene products. Herein, we report an efficient and simple green chemistry approach for the synthesis of AgNP by in‐situ reduction and capping by an eco‐friendly carbohydrate polymer, alginate dialdehyde (ADA). The UV‐Vis absorption maxima of the ADA‐capped silver nanoparticles (ADA‐AgNPs) showed a surface plasmon resonance peak at 411 nm, a peak characteristic to silver nanoparticles, within 30 min of the onset of the reaction. They were spherical, had an average diameter of 18.68±2.5 nm and had face‐centered cubic structure. Its storage stability was tested up to 90 days by monitoring its zeta potential and it was found to be stable around −35.1±1.71 mV. ADA‐AgNPs exhibited good antimicrobial properties against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) and excellent antibiofilm activity against S. aureus at its minimum inhibitory concentration of 34 μg/mL. ADA‐AgNPs showed good anticancer action against HCT‐116 cells too.
To be in Vogue: How mere proximity to high‐status neighbors affects aspirational pricing in the U.S. fashion industry
Authors: Kim Heeyon , Kim Bo Kyung
Published: November 2021

Research summary

This article examines how proximity to high‐status neighbors enables lower‐status firms to engage in aspirational pricing. While prior studies have focused on associations based on bilateral agreements, we argue that mere spatial proximity to other high‐status firms creates perceived associations, which positively affects the focal firm's aspirational pricing. Furthermore, middle‐status firms are most likely to engage in aspirational pricing because they are sufficiently similar to high‐status neighbors to expect assimilation, not contrast, effects. Our multi‐method approach based on panel data from the U.S. Vogue magazine and an experiment provides converging evidence for our arguments. Being somewhat randomly featured near the advertisements of prominent high‐status firms in Vogue positively impacts the subsequent average listed price of the focal firm's products, especially for middle‐status firms.

Managerial summary

High‐status firms tend to form relationships with other high‐status counterparts, making it difficult for lower‐status firms to ascend the status hierarchy and access status‐based benefits. This study shows that lower‐status firms may be able to obtain status‐based benefits, namely the ability to set higher prices for their products, by merely being proximate to other high‐status firms. Our analyses using data from Vogue magazine and online experiment show that having advertisements appear proximate to those of high‐status fashion firms enables the focal firm, especially middle‐status ones, to raise the prices of their products. As advertisement locations are somewhat random in that firms do not have control over determining their adjacent ads, our study highlights that lucky locations can sometimes be beneficial to disadvantage lower‐status firms.
Local Surface Chemistry Dynamically Monitored by Quantitative Phase Microscopy
Authors: Brasiliense Vitor , Audibert Jean‐Frédéric , Wu Tengfei , Tessier Gilles , Berto Pascal , Miomandre Fabien
Published: November 2021

Surface modification by photo grafting constitutes an interesting strategy to prepare functional surfaces. Precision applications, however, demand quantitative methods able to monitor and control the amount and distribution of surface modifications, which is hard to achieve, particularly in operando conditions. In this paper, a label‐free, cost‐effective, all‐optical method based on wavefront sensing which is able to quantitatively track the evolution of grafted layers in real‐time, is presented. By positioning a simple thin diffuser in the close vicinity of a camera, the thickness of grafted patterns is directly evaluated with sub‐nanometric sensitivity and diffraction‐limited lateral resolution. By performing an in‐depth kinetic analysis of the local modification of an inert substrate (glass cover slips) through photografting of arydiazonium salts, different growth regimes are characterized and several parameters are estimated, such as the grafting efficiency, density and the apparent refractive index distribution of the resulting grafted layers. Both focused and widefield‐grafting can be quantitatively monitored in real time, providing valuable guidelines to maximize functionalization efficiency. The association of a well‐characterized versatile photografting reaction with the proposed flexible and sensitive monitoring strategy enables functional surfaces to be prepared, and puts surface micro‐ to submicro‐structuration within the reach of most laboratories.