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Polyurethane (PU), as a polymer material with versatile product forms and excellent performance, is used in coatings, elastomers, adhesives, and foams widely. However, the raw materials (polyols and isocyanates) of PU are usually made using petroleum‐derived chemicals. With the concern for depletion of petroleum resources and the associated negative impact on the environment, developing technologies that can use renewable raw materials as feedstock has become a research hotspot. Lignin, as an abundant, natural, and renewable organic carbon resource, has been explored as raw material for making polyurethanes because it possesses rich hydroxyl groups on its surface. Meanwhile, compared to vegetable oils, lignin does not compete with food supply and performance of the resulting products is superior. Lignin or modified lignin has been shown to impart the polyurethane material with additional functionalities, such as UV‐blocking ability, hydrophobicity, and flame retardancy. However, the utilization of lignin has encountered some challenges, such as product isolation, heterogeneity, aggregation, steric hindrance, and low activity. This paper summarizes recent research progress on utilizing lignin and modified lignin for bio‐based polyurethane synthesis with a focus on elastomers and foams. Opportunities and challenges for application of the lignin‐based polyurethanes in various fields are also discussed. [ABSTRACT FROM AUTHOR]

By virtue of remarkable biocompatibility and their promising applications in biomedical fields, biomass‐regenerated fibers, such as wool keratin fiber and cellulose fiber, have attracted extensive attention. However, the insufficient mechanical performance still hinders their yarn manufacturing capability and further large‐scale applications. Herein, an ultra‐strong and ultra‐tough regenerated wool keratin fiber by regulating keratin conformation with high‐quality small‐size graphene (HQSGr) and mechanical training treatment (M‐HQSGr‐RWKF) is fabricated. With the assistance of mechanical training, a small addition of HQSGr (0.1 wt.%) remarkably augments the secondary structure transition from α‐helix to β‐sheet of the keratin, which delivers a tensile strength of 215.4 ± 5.2 MPa, surpassing all reported natural wool and regenerated wool or even poultry fibers. Benefiting from the excellent mechanical strength, wet‐state toughness (158.9 MJ m−3), and recoverable strain (205.0%), M‐HQSGr‐RWKF has been demonstrated as a biocompatible artificial muscle to drive the biomimetic motion, which manifests ultrahigh actuation strain greater than 100.0% and stress of 16.7 MPa. The derived ultra‐strong and ultra‐tough keratin fiber opens a new avenue for developing smart fiber from biomass resources. [ABSTRACT FROM AUTHOR]

Fabrication of fluorescent cellulose with aggregation‐induced emission (AIE) characteristics is usually achieved by grafting tetraphenylethylene (TPE) to the cellulose backbone using TPE derivatives with highly active functional groups such as carboxylic, isothiocyanate, and alkynyl groups. However, besides the complicated synthetic routes of these TPE derivatives, conversion of hydroxyl groups in the cellulose chain to more reactive groups such as amine or azide groups is usually involved, and the resulting products have a degree of substitution (DS) of TPE lower than 0.08. Herein, a facile one‐pot strategy for the grafting of a TPE group to the cellulose backbone with high DS of up to 0.22 in a CO2 switchable solvent under mild reaction conditions is reported. The hydroxyl groups in the cellulose are in situ converted to cellulose carbonate intermediately during the dissolution step. Subsequently, nucleophilic substitution between the intermediate and a halogenated TPE derivative with bromine atom as leaving group is carried out to achieve the effective grafting of TPE. The synthetic route for this promising TPE derivative is much more convenient than those of TPE derivatives reported in previous studies. This work suggests a new and facile pathway for the synthesis of high‐emission fluorescent cellulose with AIE functionality. [ABSTRACT FROM AUTHOR]

Since the commercialization of lithium‐ion batteries (LIBs) in the early 1990s, tin (Sn), antimony (Sb), and germanium (Ge)‐based anodes have attracted considerable research interest as promising candidates for next‐generation LIBs due to their high theoretical capacities, suitable operating voltages, and natural abundance. Additionally, the awareness of limited global lithium sources promoted the renaissance of sodium‐ion batteries (SIBs) in recent years. Sn, Sb, and Ge can electrochemically alloy with sodium and are regarded as promising anode candidates for high‐performance SIBs. However, these alloying/dealloying anodes suffer severe volume expansion during lithiation or sodiation processes, which is one of the biggest obstacles toward practical applications. In order to solve this problem, several strategies are developed including reducing the absolute size of particles, creating interior void space, and introducing buffer media. After more than two decades' efforts, the electrochemical performance of Sn, Sb, and Ge‐based anodes is significantly improved. Considerable studies about Sn, Sb, and Ge‐based anodes are summarized in a chronicle perspective and the brief development histories of the three anodes are outlined. With this unique review, light will be shed on the future trends of the studies on the Sn, Sb, and Ge‐based anodes for advanced rechargeable batteries. [ABSTRACT FROM AUTHOR]

Background and Purpose: Dopamine protects the duodenal mucosa. Here we have investigated the source of dopamine in gastric juice and the mechanism underlying the effects of luminal dopamine on duodenal bicarbonate secretion (DBS) in rodents.Experimental Approach: Immunofluorescence, UPLC-MS/MS, gastric incubation and perfusion were used to detect gastric-derived dopamine. Immunofluorescence and RT-PCR were used to examine the expression of dopamine receptors in the duodenal mucosa. Real-time pH titration and pHi measurement were performed to investigate DBS.Key Results: H+ -K+ -ATPase was co-localized with tyrosine hydroxylase and dopamine transporters in gastric parietal cells. Dopamine was increased in in vivo gastric perfusate after intravenous infusion of histamine and in gastric mucosa incubated, in vitro, with bethanechol chloride or tyrosine. D2 receptors were the most abundant dopamine receptors in rat duodenum, mainly distributed on the apical membrane of epithelial cells. Luminal dopamine increased DBS in a concentration-dependent manner, an effect mimicked by a D2 receptor agonist quinpirole and inhibited by the D2 receptor antagonist L741,626, in vivo D2 receptor siRNA and in D2 receptor -/- mice. Dopamine and quinpirole raised the duodenal enterocyte pHi . Quinpirole-evoked DBS and PI3K/Akt activity were inhibited by calcium chelator BAPTA-AM or in D2 receptor-/- mice.Conclusion and Implications: Dopamine in the gastric juice is derived from parietal cells and is secreted along with gastric acid. On arrival in the duodenal lumen, dopamine increased DBS via an apical D2 receptor- and calcium-dependent pathway. Our data provide novel insights into the protective effects of dopamine on the duodenal mucosa. [ABSTRACT FROM AUTHOR]

Abstract: The properties of poly(1,4‐cyclohexylenedimethylene terephthalate) (PCT) are manipulated only by tuning the steric configuration of 1,4‐cyclohexanedimethanol (CHDM). The chemical structures and compositions of PCTs are confirmed by nuclear magnetic resonance (1H NMR and 13C NMR) before their thermal and mechanical properties are investigated by differential scanning calorimeter, thermogravimetric analyzer, and dynamic mechanical analysis. Results show that the ratio of cis‐ to trans‐CHDM in PCTs has significant influences on their properties. The melting temperature of PCTs is varied from 251 to 313 °C, and the glass transition temperature is increased from 73 to 92 °C when the content of trans‐CHDM in PCTs is increased from 10% to 96%. In addition, the crystallizability of PCT is also increased with the content of trans‐CHDM. However, its thermal stability is decreased seriously when the melting temperature of PCT is higher than 280 °C. It is concluded that when the content of trans‐CHDM is lower than 50% (PCT‐10, PCT‐28, and PCT‐46), the balance of melting temperature, glass transition temperature, and thermal stability for PCT can be achieved. Just by varying the cis/trans ratio of CHDM, rather than the addition of other components, the properties of PCT can be manipulated. [ABSTRACT FROM AUTHOR]

Background: Understanding of the early immune response in severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) breakthrough infections is limited. Methods: Ninety‐eight patients with coronavirus disease 2019 (COVID‐19) breakthrough infections were divided into two groups, with intervals from receiving the second dose of inactivated vaccine to the onset of illness <60 or ≥60 days. Results: The median lymphocyte count and the median anti‐SARS‐CoV‐2 spike immunoglobulin G (IgG) and immunoglobulin M (IgM) titers were higher in the <60‐day interval group compared with the corresponding medians in the ≥60‐day interval group (p = 0.005, p = 0.001, and p = 0.001, respectively). The median interleukin‐6 (IL‐6) level in the <60‐day interval group was significantly lower than the median IL‐6 level in the ≥60‐day interval group (p < 0.001). Conclusions: Our results highlight the different anti‐SARS‐CoV‐2 spike IgG and IgM antibody titers among patients with different intervals from receiving the second dose of inactivated vaccine to the onset of illness. [ABSTRACT FROM AUTHOR]

In this paper, large‐size reeds were introduced into PBAT to prepare high‐performance biodegradable composites by high‐speed blending without compatibilizer. Subsequently, the effects of large‐size reeds on the composite properties and biodegradation behavior were further investigated. The length of the reed in composites reaches to ~1.88 mm. It was found that all composites showed larger modulus and flexural strength than PBAT, and a significant increase in heat deflection temperature. By mixing 60% reed and PBAT, the bending strength, bending modulus, and heat deflection temperature reached 23.9 ± 0.4 MPa, 1237 ± 143 MPa, and 71.8°C, respectively. Biodegradation tests showed that the primary bond‐breaking site of PBAT was the C=O group. Compared with pure PBAT, the composites exhibited more significant mass loss, decreased thermal stability, increased melting point, and decreased crystallinity during degradation. A surface erosion degradation model for the composites was proposed. The research provides a scientific basis for applying high‐performance biodegradable composites to biodegradable blister and injection molded products. [ABSTRACT FROM AUTHOR]

Covalent adaptable networks (CANs) possess multiple functions including reprocessing (or recyclability), self‐healing, welding, shape shifting, 3D printing, etc., due to the network rearrangement from dynamic bonds, and favorable performance from their cross‐linked feature, and they are supposed to be as sustainable alternatives to thermosets. However, the thermal and mechanical properties, and stability of CANs are often sacrificed for rapid network rearrangement. In this paper, fast‐reprocessing CANs with high performance are facilely constructed by in situ polymerization and dynamic cross‐linking of styrene (St), maleic anhydride (MA), and acetal diol (BHAD). The rigid and hydrophobic polymer backbone endow the materials with high glass transition temperatures, mechanical performance, and water resistance. Besides, carboxylic group‐catalyzed dual dynamic ester and acetal‐based networks exhibit faster stress relaxation and realize extrusion reprocessing. This work provides an ingenious and simple strategy of construction of CANs combining rapid network rearrangement and excellent comprehensive performance, which is beneficial for the application of CANs. [ABSTRACT FROM AUTHOR]

Based on the relaxation digital‐to‐analog converter (ReDAC) architecture and the capacitor charge/discharge function under discrete time conditions, this paper proposes a new mathematical model for the output voltage of the ReDAC to implement the unconstrained relaxation DAC (Uc‐ReDAC). The system clock calibration is not required. An adaptive probabilistic binary particle swarm optimization (AP‐BPSO) algorithm is proposed for solving the binary coding configuration problem under the Uc‐ReDAC model. Simulation results show that the 8‐bit (10‐bit) Uc‐ReDAC has an average sampling rate of 7.9 MS/s (6.76 MS/s). [ABSTRACT FROM AUTHOR]

The temperature is critical for the elimination sequence. [ABSTRACT FROM AUTHOR]

Covalent adaptable networks (CANs) exhibit recyclability such as reprocessing, but it's a challenge to address the contradiction between reprocessing rate and performance. Here, pendent aliphatic chain anhydride monoesters are innovatively introduced into epoxy CANs based on transesterification, which efficiently accelerates the reprocessing without sacrificing thermal and mechanical properties. The transesterification rate is raised on account of the flexible aliphatic chain‐promoted segment movement and dynamic transfer auto‐catalysis. When the carbon number reflecting the length of the pendent chain is 12, the epoxy CAN exhibits the fastest stress relaxation or reprocessing. Computation via molecular dynamics simulation demonstrates that the increased segmental mobility from the pendent aliphatic chains contributes to enhanced reprocessability. Interestingly, the crystallization of the pendent aliphatic chains maintains or even improves the thermal and mechanical properties. Thus, introducing a flexible and crystallizable aliphatic side chain is an innovative and efficient approach to accelerate dynamic reactions and network arrangement while improving performance. [ABSTRACT FROM AUTHOR]

In this Letter, three types of bearingless switched reluctance machines (BSRMs) with different hybrid stator structures are designed and analysed. First of all, topologies of three BSRMs, the conventional 8/10 pole, 12/14 pole BSRMs and a novel 12/12 pole BSRM with axial split phase inner stator permanent magnet structure, are given. Then, the electromagnetic performances, including the distribution of magnetic fields, suspension force and electromagnetic torque are comprehensively compared by means of 2D and 3D finite‐element method (FEM). The results based on theoretical analysis and FEM reveal that the proposed 12/12 pole BSRM would exhibit complete decoupling, shorter magnetic circuit, higher torque (power) density and suspension force than the conventional ones. Further, it is found that four degree‐of‐freedom suspension of the rotor can be realised by two‐phase suspension windings in the proposed 12/12 pole BSRM. Finally, a prototype machine is designed and manufactured to verify the validity of the topology design and electromagnetic performance. [ABSTRACT FROM AUTHOR]

An organocatalytic enantioselective conjugate addition of aryl methyl nucleophiles to a wide range of α,β-unsaturated aldehydes is developed. [ABSTRACT FROM AUTHOR]

Covalent adaptable networks (CANs) are a new type of polymers, which possess excellent performance of thermosets and reprocessability of thermoplastics. Nevertheless, it is still a challenge to realize rapid reprocessing and postadjusting (adjust properties after preparation). Herein, for the first time, a method of combining Schiff base and Diels–Alder adduct in one network is developed to achieve rapid reprocessing and postadjusting. Through the dissociation of the Diels–Alder adduct at high temperatures, the cross‐link densities of the networks are reduced, thereby accelerating the rearrangement of the networks and realizing the rapid reprocessing and self‐healing. Moreover, the reconnecting degree of network after dissociation of Diels–Alder adduct can be easily controlled by annealing; as a result, the properties of the obtained CANs are postadjustable. This work provides a simple and promising approach of achieving excellent reprocessing and postadjusting for CANs via the synergism of an associative dynamic chemistry with a dissociative dynamic chemistry. [ABSTRACT FROM AUTHOR]

Most patients with epithelial ovarian cancer ( EOC) are diagnosed at an advanced stage, and therapeutic options for these patients are limited. The identification of suitable biomarkers could be helpful for patients with EOC, who might benefit from targeted therapies even in advanced stages of the disease. Trophoblast cell surface antigen 2 ( TROP2) is highly expressed in various human malignant tumours; however, this has not been demonstrated clearly in EOC. In this study, we further evaluated whether TROP2 is a promising marker for EOC, and thus also a potential target for EOC immunotherapy. Quantitative real-time polymerase chain reaction (qPCR) and fluorescence-activated cell sorting (FACS) analysis were employed to determine TROP2 mRNA and protein expression in both human EOC and normal ovarian cell lines. Additionally, TROP2 protein expression was measured by immunohistochemistry in 128 EOC tissue samples, 21 normal ovarian tissues and 18 normal fallopian tubes. The correlations between TROP2 protein expression and patients' clinicopathological features were investigated, and survival outcomes were analysed. TROP2 mRNA and protein levels were upregulated significantly in EOC cell lines compared with normal cell lines. The protein of TROP2 was expressed in the majority of EOC tissue samples (90.6%) and overexpressed in 75 (58.6%) of the 128 tumour samples. TROP2 overexpression was correlated with relevant clinicopathological characteristics and was associated with significantly shortened overall survival and disease-free survival. Furthermore, TROP2 was an independent prognostic marker for EOCs as analysed by Cox regression. TROP2 was a potential biomarker for targeted therapy in patients with TROP2-overexpressing EOC. [ABSTRACT FROM AUTHOR]

The adoption of pest-resistant transgenic plants to reduce yield losses and decrease pesticide use has been successful. To achieve the goal of controlling both chewing and sucking pests in a given transgenic plant, we generated transgenic tobacco, Arabidopsis, and rice plants expressing the fusion protein, AaIT/GNA, in which an insecticidal scorpion venom neurotoxin ( Androctonus australis toxin, AaIT) is fused to snowdrop lectin ( Galanthus nivalis agglutinin, GNA). Compared with transgenic tobacco and Arabidopsis plants expressing AaIT or GNA, transgenic plants expressing AaIT/GNA exhibited increased resistance and toxicity to one chewing pest, the cotton bollworm, Helicoverpa armigera. Transgenic tobacco and rice plants expressing AaIT/GNA showed increased resistance and toxicity to two sucking pests, the whitefly, Bemisia tabaci, and the rice brown planthopper, Nilaparvata lugens, respectively. Moreover, in the field, transgenic rice plants expressing AaIT/GNA exhibited a significant improvement in grain yield when infested with N. lugens. This study shows that expressing the AaIT/GNA fusion protein in transgenic plants can be a useful approach for controlling pests, particularly sucking pests which are not susceptible to the toxin in Bt crops. [ABSTRACT FROM AUTHOR]

Jute fiber with high content and large aspect ratio is directly used to prepare PLA composites to show the effect on structure and properties. By comparing with bamboo powder, it is found that the large aspect ratio of jute fiber is helpful to form a crisscross structure in PLA composites to provide a strong framework. And the larger amount of jute fiber leads to the stronger framework in the PLA composites. Accordingly, the high comprehensive mechanical properties are produced of the PLA composites with jute fiber. Only through the simple blending of 70% jute fiber and PLA, the flexural strength and flexural modulus respectively reach 94.0 ± 4.4 MPa and 9116.7 ± 127.2 MPa, which obviously exceed the mechanical properties of PLA/bamboo blends. The addition of jute fiber also improves the thermal resistance of PLA composites as well as the crystallization ability and perfection of PLA. All the results exhibit the advantages of high content filling of jute fiber with large aspect ratio to modify PLA. Utilization of biomass filler with high content and large aspect ratio will provide an important methodology to expand the application capacity of fully degradable composites in many areas. [ABSTRACT FROM AUTHOR]

The transformation is efficiently achieved by an amine-catalyzed CAN-mediated single electron transfer oxidation process. [ABSTRACT FROM AUTHOR]

The title compound, C15H10O5·H2O, also known as emodin monohydrate, was isolated from the roots of Polygonum cuspidatum Sieb. et Zucc. It is an anthraquinone derivative, and all of its non-H atoms are essentially coplanar. Intra­molecular O—H⋯O hydrogen bonds and inter­molecular O—H⋯O and C—H⋯O hydrogen bonds are observed in this crystal form. The crystal structure is further stabilized by weak π–π inter­actions and hydrogen bonds to the water mol­ecule. [ABSTRACT FROM AUTHOR]

Ionic skin (I‐Skin) has the advantage of feasible compatibility with biological systems. Nevertheless, developing a stable and durable ionic skin is challenging. Here, an ionic polyurethane (i‐PU) is synthesized, which is capable of self‐healing and able to lock the ionic liquids (ILs). In detail, an ionic chain extender containing an ammonium cationic group is synthesized, followed by the polymerization to obtain the target i‐PU. Through electrostatic interaction and chain diffusion, the i‐PU can be fully self‐healed at room temperature within 400 min. Afterward, low contact angle (37°) of the i‐PU against IL and the density functional theory (DFT) calculation prove their good compatibility and strong interaction, originating from the electrostatic interaction. The Raman intensity map shows the reversible process of the enrichment and restoration of ionic concentration on the i‐PU/IL surface when external pressure is applied or released, proving stable binding of ions by ionic polymer chains. Lastly, the self‐healing I‐Skin based on the i‐PU/IL is fabricated with a wide range of pressures (0–120 kPa), fast response time (32 ms), excellent antifatigue property (2% attenuation after 1000 cycles), and remarkable sensitivity (52.4 kPa–1). [ABSTRACT FROM AUTHOR]

Reactions of polycarboxylate ligand (2,2′‐H2bpdc or H3OABDC), N‐donor auxiliary ligand (4‐bpmh) with Cd(II) salts under solvothermal conditions resulted in two coordination polymers formulated as [Cd(2,2′‐bpdc)(4‐bpmh)(H2O)]n·n(H2O) (1) and [Cd3(OABDC)2(4‐bpmh)2(H2O)4]n·2n(H2O) (2) (2,2′‐H2bpdc = diphenic acid, H3OABDC = 5‐oxyacetate isophthalic acid, and 4‐bpmh is N,N‐bis‐pyridin‐4‐ylmethylene‐hydrazine). Meanwhile, the investigations of luminescent performances and thermal stabilities suggest that the two compounds are candidate materials for the fluorescent emitting material. The assessment of their application values on the infantile bronchial pneumonia was carried out and their specific mechanism was investigated in the meantime. [ABSTRACT FROM AUTHOR]

Polymeric elastomers play an increasingly important role in the development of stretchable electronics. A highly demanded elastic matrix is preferred to own not only excellent mechanical properties, but also additional features like high toughness and fast self‐healing. Here, a polyurethane (DA‐PU) is synthesized with donor and acceptor groups alternately distributed along the main chain to achieve both intra‐chain and inter‐chain donor‐acceptor self‐assembly, which endow the polyurethane with toughness, self‐healing, and, more interestingly, thermal repair, like human muscle. In detail, DA‐PU exhibits an amazing mechanical performance with elongation at break of 1900% and toughness of 175.9 MJ m−3. Moreover, it shows remarkable anti‐fatigue and anti‐stress relaxation properties as manifested by cyclic tensile and stress relaxation tests, respectively. Even in case of large strain deformation or long‐time stretch, it can almost completely restore to original length by thermal repair at 60 °C in 60 s. The self‐healing speed of DA‐PU is gradually enhanced with the increasing temperature, and can be 1.0–6.15 µm min−1 from 60 to 80 °C. At last, a stretchable and self‐healable capacitive sensor is constructed and evaluated to prove that DA‐PU matrix can ensure the stability of electronics even after critical deformation and cut off. [ABSTRACT FROM AUTHOR]

Methyl jasmonate (MeJA) is an airborne signaling phytohormone that can induce changes in endogenous jasmonates (JAs) and cause photosynthetic responses. However, the response of these two aspects of citrus plants at different MeJA concentrations is still unclear. Four MeJA concentrations were used in two citrus varieties, Huangguogan (C. reticulata × C. sinensis) and Shiranuhi [C. reticulata × (C. reticulata × C. sinensis)], to investigate the effects of MeJA dose on the endogenous JAs pathway and photosynthetic capacity. We observed that MeJA acted in a dose‐dependent manner, and its stimulation in citrus leaves showed a bidirectional character at different concentrations. This work demonstrates that MeJA at only a concentration of 2.2 mM or less contributed to the activation of magnesium protoporphyrin IX methyltransferase (ChlM, EC 2.1.1.11) and protochlorophyllide oxidoreductase (POR, EC 1.3.1.11) and the simultaneous accumulation of Chl a and Chl b, which in turn contributed to an improved photosynthetic capacity and PSII photochemistry efficiency of citrus. Meanwhile, the inhibition of endogenous JAs synthesis by exogenous MeJA was observed. This was achieved by reducing the ratio of monogalactosyl diacylglycerol (MGDG) to diagalactosyl diacylglycerol (DGDG) and inhibiting the activities of key enzymes in JAs synthesis, especially 12‐oxo‐phytodienoic acid reductase (OPR, EC 1.3.1.42). Another noteworthy finding is that there may exist a JA‐independent pathway that could regulate 12‐oxo‐phytodienoic acid (OPDA) synthesis. This study jointly analyzed the internal hormone regulation mechanism and the external physiological response, as well as revealed the effects of exogenous MeJA on promoting the photosynthesis and inhibiting the endogenous JAs synthesis. [ABSTRACT FROM AUTHOR]

Binders play a crucial role in maintaining mechanical integrity of electrodes in lithium‐ion batteries. However, the conventional binders lack proper elasticity, and they are not suitable for high‐performance silicon anodes featuring huge volume change during cycling. Herein, a poly(siloxane imide) copolymer (PSI) has been designed, synthesized, and utilized as a binder for silicon‐based anodes. A rigidness/softness coupling mechanism is demonstrated by the PSI binder, which can accommodate volume expansion of the silicon anode upon lithiation. The electrochemical performance in terms of cyclic stability and rate capability can be effectively improved with the PSI binder as demonstrated by a silicon nanoparticle anode. [ABSTRACT FROM AUTHOR]

CuO based anodes hold a promise alternative to the commercial graphite due to their high reversible capacities, low cost, and environmental friendliness. However, drastic volume change, partial irreversibility, and poor electron conductivity yields compromised the electrochemical performance including reversible capacities, cyclic stability and rate performance. A facile scalable method is developed to synthesize CuO/C nanohybrid lithium‐ion battery anode. Copper nanoparticles are synthesized in situ using the amine based curing agent as both coordination ligand and reducing agent. The copper nanoparticles/amine based curing agent further reacts with the epoxy resin monomers, where the copper nanoparticles are incorporated into the thermosetting polymer network. Due to thermosetting nature of the epoxy polymer, agglomeration of the copper nanoparticles is effectively suppressed during the carbonization process, which are further converted to the CuO nanoparticles within the carbon matrix through heat treatment in air. Systematic structure and electrochemical performance characterizations are carefully studied. The results show that both the reversible capacities are effectively improved in comparision with the bare carbon sample. Moreover, excellent cyclic stability and high rate capability are also demonstrated by the CuO/C nanohybrid. [ABSTRACT FROM AUTHOR]

A highly efficient synthesis strategy, focusing on amide bond formation and peptide synthesis, has been developed under mild condition by employing a 2‐chloroimidazolium chloride IMesCl−Cl as a coupling reagent. This strategy exhibited wide substrate scope and good chemo‐selectivity. Notably, no significant loss of enantiopurity was observed when employing this strategy to dipeptide synthesis. This method was also successfully applied in glycine‐conjugate bile acids synthesis. A plausible formation mechanism via an active ester intermediate was proposed. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Five types of ZrO2 are used to simply establish an effective aqueous catalytic system with sulfuric acid for the hydrolysis of cellulose to sugar, respectively. By adjusting surface roughness and particle size of ZrO2, different adsorption is produced. Accordingly, following the thought to inhibit the self‐aggregation nature of cellulose, after the introduction of ZrO2 with adsorption in catalysts, the efficiency of the hydrolysis of cellulose to sugar is improved. The results show different ZrO2 can produce different effects during the hydrolysis of the cellulose with relatively low crystallinity. Under the optimal conditions, the conversion of cellulose and TRS yield reaches 95.5% and 93.6%, respectively. Through this research, it reveals the critical point to organize a feasible and useful way for the hydrolysis of cellulose to sugar with high efficiency in an aqueous system. An important theoretical and technical support is also provided for the conversion and utilization of cellulose in the future. [ABSTRACT FROM AUTHOR]

A synthetically useful approach for the synthesis of functionalized α, α‐disubstituted α‐amino acid derivatives via palladium‐catalyzed 1,7 addition of readily available aldimine esters to vinylcyclopropanes is reported. This methodology was operated under mild conditions, affording α‐allylic α‐amino esters in good to excellent yields and excellent regio‐ and stereoselectivity. This transformation displays broad functional‐group tolerance and enantioselective allylic alkylation has also been realized using a chiral phosphine ligand to provide the desired product. [ABSTRACT FROM AUTHOR]

Recent studies have found that known functions of circular RNAs (circRNAs) include sequestration of microRNAs (miRNAs) or proteins, modulation of transcription and interference with splicing, and even translation to produce polypeptides. The zebrafish model is also demonstrably similar to humans in many studies. To explore the changes in circRNAs during embryonic development and to further research the mechanism of action of circRNAs in development‐related diseases, Zebrafish embryos at the blastula period, gastrula period, segmentation period, throat stage, and incubation period were collected. Illumina deep‐sequencing technology and CircRNA Identifier (CIRI) algorithm were used to detect circRNAs. In total, we identified 1,028 circRNAs (junction reads ≥5 and p < 0.05). Considering that the function of circRNAs is related to host genes, a bioinformatics analysis revealed these differentially expressed host genes are involved in NOTCH signaling pathways, cardiovascular system development, retinal ganglion cell axon guidance, and so on. Moreover, circRNAs can participate in biological regulation through the function of miRNA sponges. TargetScan and miRanda were used to predict 73 miRNAs binding to circRNAs such as miR‐19b, miR‐124, and so on. Some miRNAs play important roles in embryogenesis. The peak expression of circRNAs is distributed at different time points, suggesting that it may be involved in embryogenesis at different stages. Our study provides a foundation for understanding the dynamic regulation of circRNA transcriptomes during embryogenesis and identifies novel key circRNAs that might control embryonic development in a zebrafish model. [ABSTRACT FROM AUTHOR]

The receptor‐tyrosine‐kinase (RTK)‐like orphan receptor 1 (ROR1) is a transmembrane glycoprotein regarded as a tumor‐associated antigen. ROR1 plays an important role in cancer development, but the detailed function of ROR1 in diffuse large B‐cell lymphoma (DLBCL) remains unclear. In this study, we first detected ROR1 expression and evaluated the relationship between ROR1 expression and the clinicopathological characteristics of DLBCL patients. Next we employed shRNA‐mediated knockdown of ROR1 in DLBCL cell line to explore the characteristics of ROR1 in DLBCL development both in vitro and in vivo. The results showed a significantly higher level of ROR1 in DLBCL tissues than in lymphatic hyperplasia tissues. High ROR1 expression was correlated with unfavorable prognosis in DLBCL patients. Furthermore, ROR1 knockdown inhibited the growth and induced the apoptosis in DLBCL cells and xenografts. In addition, shROR1 inhibited activation of the PI3K/Akt/mTOR signaling pathway, both in vitro and in vivo. Taken together, our results suggest that ROR1 is a novel prognostic marker for DLBCL survival and ROR1 significantly promotes DLBCL tumorigenesis by regulating the PI3K/Akt/mTOR signaling pathway. Targeting ROR1 may provide a promising strategy for DLBCL treatment. © 2019 BioFactors, 45(3):416–426, 2019 [ABSTRACT FROM AUTHOR]

Super‐small sized TiO2 nanoparticles are in situ co‐composited with carbon and nickel nanoparticles in a facile scalable way, using difunctional methacrylate monomers as solvent and carbon source. Good control over crystallinity, morphology, and dispersion of the nanohybrid is achieved because of the thermosetting nature of the resin polymer. The effects of the nickel nanoparticle on the composition, crystallographic phase, structure, morphology, tap density, specific surface area, and electrochemical performance as both lithium‐ion and sodium‐ion battery anodes are systematically investigated. It is found that the incorporation of the in situ formed nickel nanoparticles with certain content effectively enhances the electrochemical performance including reversible capacities, cyclic stability and rate performance as both lithium‐ion and sodium‐ion battery anodes. The experimental I‐V profiles at different temperatures and theoretical calculations reveal that the charge carriers are accumulated in the amorphous carbon regions, which act as scattering centers to the carriers and lower the carrier mobility for the composite. With increasing nickel content, the mobility of the charge carriers is significantly increased, while the number of the charge carriers maintains almost constant. The nickel nanoparticles provide extra pathways for the accumulated charge, leading to reduced scatterings among the charge carriers and enhanced charge‐carrier transportation. [ABSTRACT FROM AUTHOR]

The present study elucidates the potential role of Trop2 in tumor invasion and the promotion of epithelial‐mesenchymal transition (EMT) when binding β‐catenin in GC. The role of Trop2 in promoting EMT in GC cells was examined by a variety of experimental assays. Moreover, the underlying molecular mechanism of Trop2 in promoting EMT was studied by in vivo and in vitro assays. The Trop2 expression in relation to tumor metastasis status was detected by IHC in 248 cases of GC tissues and 86 cases of matched adjacent tissues. Trop2 promoted the metastasis and induces EMT in GC. Meanwhile, the elevated protein levels of Trop2 and mesenchymal markers were also found in the TGF‐β1‐induced EMT model in GC cells. Importantly, Trop2 physically bound and activated β‐catenin to promote EMT; moreover, Trop2 increased the accumulation of β‐catenin in the nucleus to accelerate metastasis in GC cells. Inhibition of Trop2 expression in GC cells prevented the migration and invasion of GC cells in vivo. Trop2+/vimentin+ expression was higher in GC tissues than that in matched adjacent tissues, and Trop2+/vimentin+ expression in GC was associated with the differentiation, TNM stage, and distant metastases. These sets of data reveal a novel regulatory network of Trop2 in EMT and GC metastasis, suggesting Trop2 as a useful marker for inducing EMT and metastasis of GC, which may help to lead a better understanding of the pathogenesis of the GC. Trop2 as a useful marker for inducing EMT and metastasis of GC, which may help to lead a better understanding of the pathogenesis of the GC. [ABSTRACT FROM AUTHOR]

Abstract: Cancer cells undergo comprehensive metabolic reprogramming to meet the increased requirements of energy and building blocks for proliferation. Lipin‐1, a phosphatidic acid phosphatase converting phosphatidic acid (PA) to diacylglycerol (DAG), is upregulated in lung adenocarcinoma (LUAD) cell lines and tumor tissues. In this study, we reveal high lipin‐1 expression is correlated with poor prognosis of patients with LUAD. Knockdown of lipin‐1 decreases cell viability and proliferation in LUAD cells, whereas it has less effect on nontumorigenic lung cells. Autophagy and ER stress play important roles in tumor initiation and progression. Lipin‐1 knockdown induces the initiation of autophagy while disrupts formation of autolysosome. Lipin‐1 silencing induces the activation of ER stress through the IRE1α pathway. Furthermore, we demonstrate disrupted ER homeostasis contributes to the cell phenotype, and the elevated autophagy initiation is due to the ER stress in part. For the first time, we show lack of lipin‐1 enhances the sensitivity of LUAD cells to cisplatin treatment. Our results suggest that lipin‐1 is a potential target, alone or combined with other treatment, for lung cancer therapy. [ABSTRACT FROM AUTHOR]

A novel polyolefin-based elastomer of polyolefin- graft-poly( t-butylstyrene) is synthesized from styrene moieties via graft-from anionic living polymerization. The afforded elastomer comprises a soft poly(ethylene- t-1-hexene- t-divinylbenzene) segment and a hard poly( t-butylstyrene) [P( t-BS)] segment. The polymerization proceeds via complete lithiation of the pendent styrene groups (polyolefin elastomer) and subsequent graft anionic polymerization of 4- tert-butylstyrene (2000-10 000 g mol−1). The graft-from living anionic polymerization controls the grafting size with excellent efficiency by increasing the monomer concentration. To introduce functional groups into the polymer chain-end, vinyl isoprene units are introduced into the polyolefin- graft-poly( t-butylstyrene) anion to form polyolefin- graft-[poly( t-butylstyrene)- block-polyisoprene] via living block copolymerization. Subsequent graft chain-end multicarboxyl functionalization via thiol-ene 'click' reactions introduces carboxyl groups into the [P( t-BS)] graft chain-end. The water contact angle of this multicarboxyl functionalized product exhibits a sharper decrement, which affects its hydrophilicity significantly. This process produces a novel, well-defined functionalized graft-type polyolefin-based elastomer with a high utility temperature and excellent mechanical properties. [ABSTRACT FROM AUTHOR]

ABSTRACT The bio-based polyester, poly(ethylene 2,5-furandicarboxylate) (PEF), was modified by 2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO) via copolymerization and a series of copolyesters poly(ethylene-co-2,2,4,4-tetramethyl-1,3-cyclobutanediol 2,5-furandicarboxylate)s (PETFs) were prepared. After their chemical structures and sequence distribution were confirmed by nuclear magnetic resonance (1H-NMR and 13C-NMR), their thermal, mechanical, and gas barrier properties were investigated in detail. Results showed that when the content of CBDO unit in the copolyesters was increased up to 10 mol%, the completely amorphous copolyesters with good transparency could be obtained. In addition, with the increasing content of CBDO units in the copolyesters, the glass transition temperature was increased from 88.9 °C for PET to 94.3 °C for PETF-23 and the tensile modulus was increased from 3000 MPa for PEF to 3500 MPa for PETF-23. The barrier properties study demonstrated that although the introduction of CBDO units would increase the O2 and CO2 permeability of PEF slightly, PECF-10 still showed better or similar barrier properties compared with those of PEN and PEI. In one word, the modified PEF copolyesters exhibited better mechanical properties, higher glass transition temperature, good barrier properties, and better clarity. They have great potential to be the bio-based alternative to the popular petroleum-based poly(ethylene terephthalate) (PET) when used as the beverage packaging materials. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3298-3307 [ABSTRACT FROM AUTHOR]

A biobased epoxy monomer (GA-II) derived from gallic acid for multiwalls carbon nanotubes' (MWCNTs) dispersion improvement is reported in this article. The aromatic group in its molecular structure made it to be absorbed onto the surface of MWCNTs via π-π interactions and the GA-II anchored MWCNT could be homogeneously dispersed in DGEBA matrix via sonication. That was proved by Raman and UV spectroscopy as well as scanning electron microscope. After curing reaction, the epoxy/MWCNT composites demonstrated enhanced mechanical properties, excellent thermal conductivity, and high electrical conductivity. With the addition of only 0.5 wt% GA-II modified MWCNT, the tensile strength, tensile modulus, flexural strength, and flexural modulus of the composites were improved by 28%, 40%, 22%, and 16%, respectively. The thermal and electrical conductivities were also improved from 0.15 to 0.25 W/m K (67% increased) and from 0.7 × 10−14 to 0.24 × 10−4 S cm−1 (10 orders increased). POLYM. COMPOS., 38:1640-1645, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A relay formalism is proposed herein for categorizing the interplay among reactants, target product, and catalytic center in transition-metal catalysis, an important factor that can dictate overall catalysis viability and efficiency. In this formalism, transition-metal catalysis can proceed by dissociative relay, associative covalent relay, and associative dative relay modes. An intriguing associative covalent relay process operates in rhodium(III)-catalyzed oxadiazolone-directed alkenyl C−H coupling with alkynes and allows efficient access to primary pyridinylamines. Although the primary pyridinylamine synthesis mechanism is posteriori rationalized, the relay formalism formulated herein can provide an important mechanistic conceptual framework for future catalyst design and reaction development. [ABSTRACT FROM AUTHOR]

A relay formalism is proposed herein for categorizing the interplay among reactants, target product, and catalytic center in transition-metal catalysis, an important factor that can dictate overall catalysis viability and efficiency. In this formalism, transition-metal catalysis can proceed by dissociative relay, associative covalent relay, and associative dative relay modes. An intriguing associative covalent relay process operates in rhodium(III)-catalyzed oxadiazolone-directed alkenyl C−H coupling with alkynes and allows efficient access to primary pyridinylamines. Although the primary pyridinylamine synthesis mechanism is posteriori rationalized, the relay formalism formulated herein can provide an important mechanistic conceptual framework for future catalyst design and reaction development. [ABSTRACT FROM AUTHOR]

Gastric cancer ( GC) is a multistep and multistage disease and the majority of GC cells could overexpressed one or more oncogenes. Trop2 and amphiregulin ( AREG) are both overexpressed in various epithelial cell cancers and have the role in the increases tumor cells division and metastasis. However, little is known about the function and correlation of two oncogenes coexpressed in GC. The expression level of these two genes in 791 cases of GC tissues were tested, the correlations between two genes expression and clinical pathological characteristics and overall survival in GC patients through immunohistochemistry ( IHC) were analyzed. This study also explored the mRNA expression level of two genes in 26 cases of freshly GC tissues by qRT- PCR. The results indicated that Trop2+/ AREG+ coexpression was higher in GC tissues than in adjacent tissues. Trop2+/ AREG+ protein coexpression were associated with Tumor Node Metastasis ( TNM) stage ( χ2 = 50.345, P < 0.001), tumor size ( χ2 = 40.349, P < 0.001), lymph node metastases ( χ2 = 26.481, P < 0.001), and distant metastases ( χ2 = 8.387, P = 0.039). GC patients with Trop2+ and AREG+ protein coexpression had poor overall survival rates ( HR = 3.682, 95% CI = 2.038-6.654, P < 0.001). The expression level of Trop2/ AREG were positively correlated ( r 0.254 and P < 0.001). The result of the mRNA expression was similar to that of the protein expression. Overall, Trop2 and AREG could be seen as prognostic cobiomarker in GC and combined detection of Trop2 and AREG could be viewed as helpful in predicting the prognosis of the GC patients. [ABSTRACT FROM AUTHOR]

Biodegradable polymeric nanoparticles have received growing interest as one of the most promising agents for drug delivery. In the present work, functional and core-crosslinked poly(ethylene glycol) with poly(ϵ-caprolactone) (PEG5k-PCL10k) block copolymer and lecithin as biodegradable polymer doped with polyaniline was used to assemble nanoparticles which were prepared for targeted delivery and controlled release of cisplatin. The morphology of the polyaniline nanoparticles was determined by dynamic light scattering and the prepared nanoparticles showed a size of 83(±1) nm and a uniform spherical shape. For targeting to HER2 receptors, Herceptin was applied to guide the nanoparticles to breast cancer cells. Studies on cellular uptake and drug release of the nanocarriers showed that the prepared nanoparticles were efficiently taken up by breast cancer cells and the drug was released efficiently under acidic conditions when exposed to a near-infrared laser (808 nm, 1.54 W) for 5 min. Our research highlights the great potential of near-infrared light and pH dual-responsive release by core-crosslinked nanoparticles in nanobiomedicine. [ABSTRACT FROM AUTHOR]

A series of pyrrolopyridinones were prepared by using N-Boc-pyrrole-2-carbaldehyde as a starting material in an Ugi reaction followed by an acid-mediated indole cyclization to result in the formation of a new C-C bond. Changes to the other starting materials in this Ugi/indole cyclization reaction sequence extended the scope of this method to include a nucleophilic substitution reaction and an Ugi/deprotection/cyclization (UDC) strategy, which provided access to two new series of heterocyclic compounds. This method represents a facile and efficient one-pot procedure for the preparation of pyrrolopyridinones under acidic conditions. [ABSTRACT FROM AUTHOR]

A previously elusive RuII-catalyzed N−N bond-based traceless C−H functionalization strategy is reported. An N-amino (i.e., hydrazine) group is used for the directed C−H functionalization with either an alkyne or an alkene, affording an indole derivative or olefination product. The synthesis features a broad substrate scope, superior atom and step economy, as well as mild reaction conditions. [ABSTRACT FROM AUTHOR]

The use of enaminones as effective synthons for a directed C−H functionalization is reported. Proof-of-concept protocols have been developed for the RhIII-catalyzed synthesis of naphthalenes, based on the coupling of enaminones with either alkynes or α-diazo-β-ketoesters. Two inherently reactive functionalities (hydroxy and aldehyde groups) are integrated into the newly formed cyclic framework and a broad range of substituents are tolerated, rendering target products readily available for further elaboration. [ABSTRACT FROM AUTHOR]

The use of enaminones as effective synthons for a directed C−H functionalization is reported. Proof-of-concept protocols have been developed for the RhIII-catalyzed synthesis of naphthalenes, based on the coupling of enaminones with either alkynes or α-diazo-β-ketoesters. Two inherently reactive functionalities (hydroxy and aldehyde groups) are integrated into the newly formed cyclic framework and a broad range of substituents are tolerated, rendering target products readily available for further elaboration. [ABSTRACT FROM AUTHOR]

The bio-based diamine and epoxy monomer derived from isosorbide are synthesized. Especially, the diamine is obtained using microwave assistant thiol-ene coupling reaction in the aqueous media and the influence of reaction parameters, such as initiator content and reaction time, are investigated. After curing the synthesized epoxy monomer together with the diamine, properties of the cured resins are studied by differential sscanning calorimetry, dynamic mechanical analysis, and thermogravimetric analyzer. Results demonstrate that the cured resin has good shape fixity, good shape recovery, and satisfied thermal stability despite the presence of heteroatoms. This bio-based epoxy resin shows great potential to be used as a candidate for shape memory material. Considering the bio-based feedstock and environmental friendly synthetic process, a "green + green" strategy to prepare thermosetting resins with advanced properties is provided in this paper. [ABSTRACT FROM AUTHOR]

Graphene-doped Fe3O4 nanocomposites were prepared by a solvothermal reaction of an iron source with graphene. The nanocomposites were characterized by transmission electron microscopy, atomic force microscopy, X-ray diffraction, superconducting quantum interference, Raman spectroscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. This nanomaterial has been used as a magnetic solid-phase extraction sorbent to extract trace brominated flame retardants from environmental waters. Various extraction parameters were optimized including dosage and reusability of the nanocomposites, and pH of sample matrix. The reliability of the magnetic solid-phase extraction protocol based on graphene-doped Fe3O4 nanocomposites was evaluated by investigating the recoveries of 2,4,6-tribromophenol, tetrabromobisphenol A, 4-bromodiphenyl ether, and 4,4ʹ-dibromodiphenyl ether in water samples. Good recoveries (85.0-105.0%) were achieved with the relative standard deviation ranging from 1.1-7.1%. Moreover, it is speculated from characterization and magnetic solid-phase extraction experiment that there is not only π-π stacking but also possible hydrophobic interaction between the graphene-doped Fe3O4 nanocomposites and analytes. [ABSTRACT FROM AUTHOR]