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Three ω‐alkenyltrimethylsilanes of different alkenyl moieties, i.e., 3‐butenyltrimethylsilane, 5‐hexenyltrimethylsilane, and 7‐octenyltrimethylsilane, are copolymerized with propylene over a heterogeneous Ziegler‐Natta catalyst. The experimental results reveal that, at odds with what the molecular volumes will foretell, 5‐hexenyltrimethylsilane top the three ω‐alkenyltrimethylsilanes in incorporation rate into PP while 3‐butenyltrimethylsilane becomes the most sluggish of the three. This comonomer incorporation rate order is in line with that of ω‐alkenylmethyldichlorosilanes in copolymerization with propylene‐synthesizing long‐chain‐branched PP (LCB‐PP), pointing to a peculiar alkenyl length effect on comonomer incorporation rate for these comonomers. DFT simulation is then applied to seek energetic basis in coordination‐insertion for such an effect. It is revealed that complexation abilities of the three ω‐alkenyltrimethylsilanes decrease in the following order: 3‐butenyltrimethylsilane > 5‐hexenyltrimethylsilane > 7‐octenyltrimethylsilane, in line with their molecular sizes. However, the insertion energy barriers increase in the order of: 5‐hexenyltrimethylsilane < 7‐octenyltrimethylsilane < 3‐butenyltrimethylsilane. The repulsive interaction between the bulky trimethylsilane functionality of ω‐alkenyltrimethylsilanes and growing PP chain is found to contribute significantly to the insertion energy barrier, which grows disproportionally large with 3‐butenyltrimethylsilane. The current discovery will be conducive to understanding the more complex ω‐alkenylmethyldichlorosilane/propylene copolymerization that synthesizes the industrially important LCB‐PP. [ABSTRACT FROM AUTHOR]

Transplantation of a synthetic polymer nerve conduit carrying stem cells is promising for treating peripheral nerve injury. In this study, a micropatterned inner surface of polycaprolactone (PCL) nerve conduit cellularized with nasal respiratory mucosa‐derived ectoderm mesenchymal stem cells (EMSCs) is adopted for peripheral nerve regeneration. The PCL microstructure grating is fabricated by soft nanoimprint lithography (NIL), whose templates can be easily transferred from the Ebeam photoresist pattern. The most suitable microstructure is carefully chosen to support EMSCs alignment and nerve regeneration. In vitro, the micropatterned PCL nerve conduit greatly enhanced the directional alignment of EMSCs and the MBP and S100 expression of myelin proteins. Additionally, the micropatterned conduit preseeded with EMSCs significantly stimulated the axon‐directed extension of neural stem cells. In vivo, micropatterned PCL conduits cotransplanted with EMSCs enhanced motor function and promoted sciatic nerve regeneration and extension in a rat model of sciatic nerve defect. Taken together, this "all‐in‐one" nerve guidance conduit makes sciatic nerve regeneration and morphological repairing accelerated, which has a potential clinical application in neural tissue engineering. [ABSTRACT FROM AUTHOR]

Summary: This work aimed to evaluate the synergistic effect of petit‐high pressure carbon dioxide (p‐HPCD) and cinnamon (Cinnamomum cassia) essential oil (CEO) against Salmonella typhimurium. The results showed synergetic antibacterial activity of p‐HPCD and CEO. After treatment with p‐HPCD and CEO with a final concentration of 0.03125% under 1.3 MPa at 30 °C for 5 h, the population of S. typhimurium was decreased by 6.22 log10 CFU/mL, significantly higher than p‐HPCD or CEO alone. The combined treatment induced severe cellular changes in S. typhimurium, including cell membrane disruption, decreased intracellular protein and ATP, and intracellular reactive oxygen species (ROS) generation. Moreover, p‐HPCD + CEO treatment significantly inhibited the expression of virulence genes including fliC, hilA, invI and ssrA, indicating that p‐HPCD + CEO can reduce the production of virulence factors in S. typhimurium. This study provides a new approach to the application of p‐HPCD and CEO in food processing and preservation. [ABSTRACT FROM AUTHOR]

The rhizosphere is an important hotspot of soil microbial activity, diversity, and functions. Despite being a microbial hotspot, studies have seldom addressed the differences in the response of the microbial community in bulk and rhizosphere soils to domestic animal disturbance. Here, we investigated grassland disturbance by physical uprooting behaviours of Tibetan pigs (Sus scrofa domesticus) on bacterial taxonomy and functions in three soil types: Histosols, Fluvisols, and Gleysols which are dominant on the Qinghai‐Tibet Plateau. We found that after 8 years of continued disturbance, compared to the undisturbed sites, disturbance consistently reduced rhizosphere bacterial α diversity (by 34.6% on average), restructured taxonomic communities, and weakened their carbon substrate utilization capacities in all soil types. The relative abundance of the phyla Proteobacteria, Actinobacteria, and Bacteriodetes increased, but the relative abundance of Acidobacteria, Chloroflexi, and Nitrospirae decreased in the rhizosphere under disturbance. In contrast, most detected taxonomic changes in bulk soils were minor, and their changing directions were divergent among studied soil types. Compared to the undisturbed, carbon utilization potential by rhizosphere microbes decreased under disturbance and the decrease extent was stronger (by 30.4% on average) than that in bulk soil. The strengthened environmental filtering, imposed by the significant reduction of soil water‐holding capacity and nutrient contents as well as the physical destruction of soil aggregates after disturbance, provided mechanistic insight into the extensive microbial restructuring within the rhizosphere. These results may have implications for recognizing changed root‐microbe interactions and ecological processes in disturbed soils for better understanding soil ecology under intensified herding activities. [ABSTRACT FROM AUTHOR]

Nuclear receptors (NRs) are a superfamily of transcription factors which sense hormonal signals or nutrients to regulate various biological events, including development, reproduction, and metabolism. Here, this study identifies nuclear receptor subfamily 2, group F, member 6 (NR2F6), as an important regulator of hepatic triglyceride (TG) homeostasis and causal factor in the development of non‐alcoholic fatty liver disease (NAFLD). Adeno‐associated virus (AAV)‐mediated overexpression of NR2F6 in the liver promotes TG accumulation in lean mice, while hepatic‐specific suppression of NR2F6 improves obesity‐associated hepatosteatosis, insulin resistance, and methionine and choline‐deficient (MCD) diet‐induced non‐alcoholic steatohepatitis (NASH). Mechanistically, the fatty acid translocase CD36 is identified as a transcriptional target of NR2F6 to mediate its steatotic role. NR2F6 is able to bind directly onto the CD36 promoter region in hepatocytes and increases the enrichment of nuclear receptor coactivator 1 (SRC‐1) and histone acetylation at its promoter. Of pathophysiological significance, NR2F6 is significantly upregulated in the livers of obese mice and NAFLD patients. Moreover, treatment with metformin decreases NR2F6 expression in obese mice, resulting in suppression of CD36 and reduced hepatic TG contents. Therefore, these results provide evidence for an unpredicted role of NR2F6 that contributes to liver steatosis and suggest that NR2F6 antagonists may present a therapeutic strategy for reversing or treating NAFLD/NASH pathogenesis. [ABSTRACT FROM AUTHOR]

Activity of transcriptional co‐activator with PDZ binding domain (TAZ) protein is strongly implicated in the pathogenesis of human cancer and is influenced by tumor metabolism. High levels of lactate concentration in the tumor microenvironment as a result of metabolic reprogramming are inversely correlated with patient overall survival. Herein, we investigated the role of lactate in the regulation of the activity of TAZ and showed that glycolysis‐derived lactate efficiently increased TAZ expression and activity in lung cancer cells. We showed that the reactive oxygen species (ROS) generated by lactate‐fueled oxidative phosphorylation (OXPHOS) in mitochondria activated AKT and thereby inhibited glycogen synthase kinase 3 beta/beta‐transducin repeat‐containing proteins (GSK‐3β/β‐TrCP)‐mediated ubiquitination and degradation of DNA methyltransferase 1 (DNMT1). Upregulation of DNMT1 by lactate caused hypermethylation of TAZ negative regulator of the LATS2 gene promoter, leading to TAZ activation. Moreover, TAZ binds to the promoter of DNMT1 and is necessary for DNMT1 transcription. Our study showed a molecular mechanism of DNMT1 in linking tumor metabolic reprogramming to the Hippo‐TAZ pathway and functional significance of the DNMT1‐TAZ feedback loop in the migratory and invasive potential of lung cancer cells. [ABSTRACT FROM AUTHOR]

In the present work, the influences of different silane coupling agents (SCA) on the rheological behaviors of Bent/NBR nanocomposites during the curing process were investigated. The nanocomposites were prepared with a green method which is simple and free of organic solvents. The dispersion state and filler–polymer interfaces were analyzed with XRD, TEM, and SEM while rheological behaviors of the nanocomposites were explored with a rubber processing analyzer (RPA). (3‐Mercaptopropyl)trimethoxysilane (MPTMS) and bis[3‐(triethoxysilyl)propyl] tetrasulfide (TESPT) both improved the dispersion state of bentonite in the matrixes significantly. MPTMS increased the crosslinking density by forming single sulfur bonds while TESPT worked as a plasticizer and delayed the formation of crosslinking during curing process. [3‐(2‐Aminoethylamino)propyl]triethoxysilane (AEAPTMS) led to reversible filler–rubber interactions, which was the main reason for the low elastic torque of the vulcanized nanocomposites. J. VINYL ADDIT. TECHNOL., 25:236–242, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

ABSTRACT: Scale deposits exist widely in industrial water‐cooling systems and oil‐production systems, causing severe damage to the equipment. The most effective way to prevent the formation of scale has been to use an inhibitor. The use of a hyperbranched polymer as an inhibitor, however, has rarely been reported. In this study, we prepared a hydroxyl‐terminated hyperbranched polyester (HBPE–OH) with trimethyloypropane as the core and 2,2‐bis(hydroxymethyl)propionic acid as an AB2 monomer. The HBPE–OH was then modified with succinic anhydride to obtain the carboxyl‐terminated hyperbranched polyester (HBPE–COOH). The effects of the dosage, Ca2+ concentration, pH value, and temperature of the system on the inhibition efficiency were investigated when HBPE–COOH was used as an inhibitor of calcium carbonate (CaCO3) scale. HBPE–COOH acted as a good antiscaling inhibitor for CaCO3; when the polyester concentration was 200 mg/L, the scale inhibition rate exceeded 70%. Scanning electron microscopy and X‐ray powder diffraction demonstrated that the mechanism of inhibition was the disturbance of the growth of the crystals and modification of the crystal morphology by the hyperbranched polyester. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46292. [ABSTRACT FROM AUTHOR]

Ecological stoichiometry provides a powerful tool for integrating microbial biomass stoichiometry with ecosystem processes, opening far-reaching possibilities for linking microbial dynamics to soil carbon (C) metabolism in response to agricultural nutrient management. Despite its importance to crop yield, the role of phosphorus (P) with respect to ecological stoichiometry and soil C sequestration in paddy fields remains poorly understood, which limits our ability to predict nutrient-related soil C cycling. Here, we collected soil samples from a paddy field experiment after seven years of superphosphate application along a gradient of 0, 30, 60, and 90 (P-0 through P-90, respectively) kg P·ha-1·yr-1 in order to evaluate the role of exogenous P on soil C sequestration through regulating microbial stoichiometry. P fertilization increased soil total organic C and labile organic C by 1-14% and 4-96%, respectively, while rice yield is a function of the activities of soil ß-1,4-glucosidase (BG), acid phosphatase (AP), and the level of available soil P through a stepwise linear regression model. P input induced C limitation, as reflected by decreases in the ratios of C:P in soil and microbial biomass. An eco-enzymatic ratio indicating microbial investment in C vs. P acquisition, i.e., ln(BG) : ln(AP), changed the ecological function of microbial C acquisition, and was stoichiometrically related to P input. This mechanism drove a shift in soil resource availability by increasing bacterial community richness and diversity, and stimulated soil C sequestration in the paddy field by enhancing C-degradation-related bacteria for the breakdown of plant-derived carbon sources. Therefore, the decline in the C:P stoichiometric ratio of soil microorganism biomass under P input was beneficial for soil C sequestration, which offered a "win-win" relationship for the maximum balance point between C sequestration and P availability for rice production in the face of climate change. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the synthesis of a thermally responsive rod-coil poly[poly(N-isopropylacrylamide)-b-polyfluorene-b-poly(N-isopropylacrylamide)] triblock copolymer via atom transfer radical polymerization from an end-functionalized macroinitiator. Results of the study showed that the polymer underwent a phase transition in the region of 25-45°C. It also observed the failure of polymer to show complete reversible behavior upon heating and cooling.

Revealing interdisciplinary patterns is a cornerstone for the continued evolution of research, education, and societal progress, providing a scaffold upon which to build a more collaborative and integrated approach to knowledge creation. This study presents a novel approach to identifying and analyzing the critical year for interdisciplinary citations (CYIC), which was defined as the year in which qualitative change in interdisciplinary knowledge flow occurred. We conducted two experiments using a Chinese paper dataset spanning 106 disciplines from 1992 to 2022, with the first to pinpoint the occurrence of CYICs and the second to examine three patterns of interdisciplinarity following these CYICs. Our findings revealed that 85% of disciplines exhibit CYICs, often corresponding with a transition from unidirectional output to reciprocal knowledge cooperation. Furthermore, we found that datasets after CYICs are generally characterized by increased interdisciplinarity of knowledge, albeit without a corresponding rise in the interdisciplinarity of disciplines or interdisciplinary diversity. Our results suggest that policy shifts and societal needs are pivotal in driving the formation of interdisciplinary collaborations, as exemplified by the surge in mutual interdisciplinary citations in response to China's poverty alleviation efforts and western development policies. [ABSTRACT FROM AUTHOR]

Effects of different silane coupling agents on clay surface modification were studied. Herein, functionalized superfine kaolin was compounded with starch–chitosan (SCS) to prepare starch–chitosan‐functionalized superfine kaolin composite. The characterization results showed that kaolin (K) was successfully modified; the composite formed a dense intercalated structure. The glass‐transition temperature (Tg) was measured by differential scanning calorimetry and dynamic mechanical analysis. It decreased by 60 °C which attested the crystallinity of SCS. The results of thermogravimetric analysis showed that the fastest weight‐loss temperature (Tmax) was elevated by over 50 °C for composites. Mechanical properties of the composites were explored by electronic universal testing machine. Tensile strength and elongation of composites were improved by 4.7 and 10.9 times. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48050. [ABSTRACT FROM AUTHOR]

In this study, hyperbranched polyether (HBP) with terminal hydroxyl was synthesized from tetrahydrofuran and glycidol by cationic open‐loop polymerization and then modified by 2‐phosphono‐butane‐1,2,4‐tricarboxylic acid to introduce carboxyl and phosphorus to improve corrosion and scale inhibition. The structure of the products (HBPs) was determined by FTIR and 1H‐NMR. The scale inhibition efficiency (E) of calcium carbonate and calcium sulfate reached 99.74 and 97.10% at a concentration of 20 mg/L. X‐ray diffraction and scanning electron microscopy were used to examine crystal type and morphology. The addition of scale inhibitors can inhibit the growth of the calcium scale crystal and destroy the crystal structure. The corrosion inhibition rate of HBPs can reach 72.98% when dosage was 150 mg/L. Polarization curve showed that HBPs was a kind of mixed corrosion inhibitor. The adsorption of HBPs on the surface of carbon steel conformed to Langmuir adsorption, which formed physical adsorption film and inhibited the corrosion process. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48041. [ABSTRACT FROM AUTHOR]