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Background: Alzheimer's disease (AD) is a degenerative neurological disorder. Recent studies have indicated that histone deacetylases (HDACs) are among the most prominent epigenetic therapy targets and that HDAC inhibitors have therapeutic effects on AD. Here, we identified sodium valproate (VPA), a pan-HDAC inhibitor, and WT161, a novel HDAC6 selective inhibitor, as potential therapeutic agents for AD. Underlying molecular mechanisms were investigated. Methods: A cellular model, N2a-APPswe, was established via lentiviral infection, and the APPswe/PSEN1dE9 transgenic mouse model was employed in the study. LC–MS/MS was applied to quantify the concentration of WT161 in the mouse brain. Western blotting, immunohistochemical staining, thioflavin-S staining and ELISA were applied to detect protein expression in cells, tissues, or serum. RNA interference was utilized to knockdown the expression of specific genes in cells. The cognitive function of mice was assessed via the nest-building test, novel object recognition test and Morris water maze test. Results: Previous studies have focused mainly on the impact of HDAC inhibitors on histone deacetylase activity. Our study discovered that VPA and WT161 can downregulate the expression of multiple HDACs, such as HDAC1 and HDAC6, in both AD cell and mouse models. Moreover, they also affect the expression of APP and APP secretases (BACE1, PSEN1, ADAM10). RNA interference and subsequent vitamin C induction further confirmed that the expression of APP and APP secretases is indeed regulated by HDAC1 and HDAC6, with the JNK pathway being the intermediate link in this regulatory process. Through the above pathways, VPA and WT161 effectively reduced Aβ deposition in both AD cell and mouse models and significantly improved cognitive function in AD mice. Conclusions: In general, we have discovered that the HDAC6-JNK-APP secretases cascade is an important pathway for VPA and WT161 to exert their therapeutic effects on AD. Investigations into the safety and efficacy of VPA and WT161 were also conducted, providing essential preclinical evidence for assessing these two epigenetic drugs for the treatment of AD. [ABSTRACT FROM AUTHOR]

Unconventional reservoirs usually contain many weak surfaces such as faults, laminae and natural fractures, and effective activation and utilization of these weak surfaces in reservoirs can significantly improve the extraction effect. In hydraulic fracturing, when the artificial fracture approaches the natural fracture, the natural fracture would be influenced by both the original in-situ stress field and the hydraulic fracturing-induced stress field. In this paper, the hydraulic fracturing-induced stress field is calculated based on the relative position of hydraulic fracture and natural fracture, the original in-situ stress, the net pressure inside the hydraulic fracture and the pore pressure of the formation. Furthermore, the stability model of the natural fracture is established by combining the Mohr-Coulomb rupture criterion, and extensive parametric studies are conducted to explore the impact of each parameter on the stability of the natural fracture. The validity of the proposed model is verified by comparing with the reservoir characteristics and fracturing process of the X-well 150e155 formation in the Songliao Basin. It is found that the stress field induced by the hydraulic fracture inhibits the activation of the natural fracture after the artificial fracture crossed the natural fracture. Therefore, for similar reservoirs as X-well 150e155, it is suggested to connect natural fractures with hydraulic fractures first and then activate natural fractures which can effectively utilize the natural fractures and form a complex fracture network. [ABSTRACT FROM AUTHOR]

This article discusses a case of oculogyric crisis (OGC) in a patient with Wilson's disease (WD). The patient, a 30-year-old Chinese female, presented with walking difficulties, dysarthria, and sustained upward gaze of both eyes. The article provides a detailed description of the patient's symptoms and clinical findings, including video footage of the OGC attacks. The patient was diagnosed with WD based on copper biochemical examination, brain magnetic resonance imaging (MRI), and genetic testing. The article also discusses the etiology and mechanism of OGC in WD, as well as its occurrence in other inherited metabolic and neurodegenerative diseases. [Extracted from the article]

Research into automatically searching for an optimal neural network (NN) by optimisation algorithms is a significant research topic in deep learning and artificial intelligence. However, this is still challenging due to two issues: Both the hyperparameter and architecture should be optimised and the optimisation process is computationally expensive. To tackle these two issues, this paper focusses on solving the hyperparameter and architecture optimization problem for the NN and proposes a novel light‐weight scale‐adaptive fitness evaluation‐based particle swarm optimisation (SAFE‐PSO) approach. Firstly, the SAFE‐PSO algorithm considers the hyperparameters and architectures together in the optimisation problem and therefore can find their optimal combination for the globally best NN. Secondly, the computational cost can be reduced by using multi‐scale accuracy evaluation methods to evaluate candidates. Thirdly, a stagnation‐based switch strategy is proposed to adaptively switch different evaluation methods to better balance the search performance and computational cost. The SAFE‐PSO algorithm is tested on two widely used datasets: The 10‐category (i.e., CIFAR10) and the 100−category (i.e., CIFAR100). The experimental results show that SAFE‐PSO is very effective and efficient, which can not only find a promising NN automatically but also find a better NN than compared algorithms at the same computational cost. [ABSTRACT FROM AUTHOR]

Delayed judgment of learning (JOL) is a widely used metacognitive monitoring strategy that can also enhance learning outcomes. However, the potential benefits of delayed JOL on subsequent learning of new material, known as the forward effect of delayed JOL, and its stability and underlying mechanisms have yet to be fully explored. In this study, we investigated the forward effect of delayed JOL using previously unexamined word pair materials and explored the boundary conditions of this effect by manipulating the difficulty of the materials. We also examined this effect within the context of category learning. Our findings demonstrate that delayed JOL significantly enhanced the retention of new information (Experiment 1A), while the forward effect of the delayed JOL occurred only for material with a certain degree of difficulty rather than for easy material (Experiment 1B). These findings were extended and replicated using category learning (Experiment 2). These results suggest that delayed JOL can be used as a preparation strategy for subsequent learning, particularly when faced with challenging materials. Our study provides novel insights into the potential benefits and limitations of delayed JOL and contributes to our understanding of the underlying mechanisms that govern metacognitive monitoring and learning strategies. [ABSTRACT FROM AUTHOR]

Empathy has garnered increasing recognition as a pivotal component of teacher–student interactions and a notable determinant of student achievement. Nevertheless, the exact impact of empathy on teacher–student interactions remains elusive, despite research endeavors into the neural mechanisms of teacher empathy. Our article examines the cognitive neural processes of teacher empathy during various forms of teacher–student interactions. To this end, we first present a concise review of theoretical considerations related to empathy and interactions, followed by an extensive discussion of teacher–student interactions and teacher empathy through both "single-brain" and "dual-brain" perspectives. Drawing on these discussions, we propose a potential model of empathy that integrates the affective contagion, cognitive evaluation, and behavior prediction aspects of teacher–student interactions. Finally, future research directions are discussed. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common malignancy in women worldwide, and the discovery of new effective breast cancer therapies with lower toxicity is still needed. We screened a series of chalcone derivatives and found that MY11 ((E)-1-(2-hydroxy-4,6-dimethoxyphenyl)-3-(4-piperazinylphenyl) prop-2-en-1-one) had the strongest anti-breast cancer activity. MY11 inhibited the growth of MDA-MB-231 and MCF-7 breast cancer cells by arresting the cell cycle and promoting apoptosis, through regulation of the cell cycle and apoptosis-related proteins. PDTC (Pyrrolidinedithiocarbamate ammonium), a specific inhibitor of the NF-κB pathway, abolished the inhibitory effect of MY11 treatment. NF-κB has been shown to regulate PUMA-dependent apoptosis. Our in vitro studies demonstrated that MY11 promoted breast cancer cell apoptosis by activating the NF-κB/PUMA/mitochondrial apoptosis pathway (including Bcl-2, Bax, and Caspase-9). MY11 also inhibited tumor growth in an orthotopic breast cancer mouse model by inducing apoptosis through the NF-κB signaling pathway, importantly, with minimal toxicity. In addition, MY11 was found by docking analysis to bind to p65, which might enhance the stability of the p65 protein. Taken together, our findings indicate that MY11 exerts a significant anticancer effect in breast cancer and that it may be a potential candidate for the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

Background: Heat stroke is a potentially fatal condition that is caused by elevated core temperature. Guillain–Barré syndrome (GBS) induced by heat stroke is extremely rare and has only been reported in few case reports. The purpose of this case study was to evaluate the clinical symptoms, neuroelectrophysiological and imageological features of GBS after heat stroke. Methods: We reviewed our hospital records and previously published reports to find the cases of GBS after heat stroke. The clinical, imageological, and electrophysiological profiles, treatment and prognosis were presented and analyzed. Results: We retrieved three cases of GBS induced by heat stroke from our hospital, which presented as lesions on multiple cranial and peripheral nerves and albuminocytologic dissociation in the cerebrospinal fluid. All of these patients had disorders of consciousness at the early stage of heat stroke and a "pseudo-recovery period" after they recovered from coma after heat stroke. After immunoglobulin administration and immunoregulation therapy, these patients' neurological deficiencies were relieved significantly. But there are still disabilities and almost totally reliant on others. Conclusions: The number of the cases of GBS induced by HS reported in this study has been the most in the recent 5 years. Clinicians should pay attention to patients with heat stroke with sustained coma and the sudden quadriplegia. Early, exact and timely diagnosis and treatment of GBS need to be performed, to accelerate recovery and improve prognosis. [ABSTRACT FROM AUTHOR]

Background: Metastasis is the leading cause of death among breast cancer patients. MicroRNA-134 has been reported to have a tumor-suppressive role in breast cancer. Ruyiping (RYP), a traditional Chinese formula, has been shown with the ability to reduce breast cancer metastasis in pre-clinical studies. This present study was designed to examine whether miR-134 was involved in RYP-inhibited breast cancer metastasis. Methods: The expression of SLUG, E-Cadherin, N-Cadherin and miR-134 in MDA-MB-231 and 4 T1 cells treated with RYP or vehicle control were determined by quantitative realtime-PCR and western blot. Invasiveness determined by transwell assay as well as SLUG gene expression determined by qPCR were detected in cells transfected with chemically synthesized miR-134 mimics or inhibitors. BALB/c mice were injected with 4 T1 cells orthotopically and fed with RYP through gavage. Breast tumor growth, metastasis and tumor expression of EMT markers were detected. Results: Compared with the control, Ruyiping formula significantly inhibited SLUG-regulated breast cancer cells invasion. MiR-134 was induced by RYP in vitro and in vivo and was able to suppress SLUG by targeting its 3'UTR. RYP suppressed SLUG expression and cell invasion through miR-134. In 4 T1 tumor-bearing mice, RYP significantly inhibited 4 T1 tumor growth and lung metastasis, increased the levels of miR-134 and epithelial marker while decreased the levels of SLUG and mesenchymal marker. Conclusion: Our data uncovered that Ruyiping formula exerts an anti-metastatic activity against breast cancer cells by regulating SLUG through miR-134. MiR-134-SLUG axis might be a promising strategy in breast cancer therapy. [ABSTRACT FROM AUTHOR]

In comparison with traditional inorganic electrochromic materials, organic polymers offer advantages such as fast switching speed, flexibility, lightweightness, low cost and nontoxicity, solution‐processability, and color tunability. Herein, a series of hyper‐branched copolymers are synthesized from triphenylamine and 3,4‐ethylenedioxythiophene with different feed ratios via iron(III) chloride (FeCl3)‐mediated oxidative polymerization. The resultant organic‐soluble polymers are easily processable and their corresponding electrochromic devices are found to be stable with limited degradation upon 2500 cycles. In addition to their facile synthesis to achieve solution‐processable polymers, studies also show that the polymers exhibit multielectrochromic properties and give rise to five colored states upon oxidative‐doping by applying an external voltage between 0 and 2.0 V, providing an interesting example of polymers with unique electrochromic switching among up to five colors, from yellow at the neutral state, to pale green, pale purple, orange, and finally gray. [ABSTRACT FROM AUTHOR]

Maternal exercise is crucial for promoting the health of the offspring. Previous studies showed that long-term maternal exercise improves energy metabolism during pregnancy. Whether swimming exercise can reverse the metabolic disorders caused by high-fat exposure in the early life of the offspring is yet to be elucidated. Three-week-old C57BL/6 female mice were randomly assigned to the standard chow diet group (SC), standard chow diet and exercise group (SC-Ex), high-fat diet group (HFD), and high-fat diet and exercise group (HFD-Ex). After swimming intervention for 13 weeks, male and female mice were caged, and the exercise intervention lasted until delivery. Then, the mothers were fed standard chow diet. A total of 8 offsprings/group were randomly selected after 4 weeks of lactation for GTT and ITT. After body composition analysis, the mice were sacrificed to obtain specimens. The levels of metabolism factors and IL-6 were measured by suspension microarray. Subsequently, 15 min after starting the GTT and ITT, the curve detected significant difference between the HFD and other groups. The body fat percentage of the HFD-Ex offspring was significantly lower than that of HFD offspring (p < 0.05) irrespective of the gender. The levels of IL-6 and TG in the male offspring in the HFD-Ex group were improved significantly (p < 0.05). Compared to the HFD offspring, serum glucose and GIP in the female offspring in the HFD-Ex group was significantly reduced (p < 0.05). Long-term exercise of the mother effectively improved the metabolic disorder caused by high-fat exposure in the infant offspring. Thus, the metabolic inheritance of the offspring is gender-dependent; the maternal metabolism can make male offspring genetically susceptible. [ABSTRACT FROM AUTHOR]

Sarsasapogenin‐AA13(AA13), a sarsasapogenin derivative, exhibited good neuroprotective and anti‐inflammatory activities in vitro and therapeutic effects on learning and memory dysfunction in amyloid‐β‐injected mice. A sensitive UPLC–MS/MS method was developed and validated to quantitatively determine AA13 in rat plasma and was further applied to evaluate the pharmacokinetic behaviour of AA13 in rats that were administered AA13 intravenously and orally. This method was validated to exhibit excellent linearity in the concentration range of 1–1000 ng/mL. The lower limit of quantification was 1 ng/mL for AA13 in rat plasma. Intra‐day accuracy for AA13 was in the range of 90–114%, and inter‐day accuracy was in the range of 97–103 %. The relative standard deviation of intra‐day and inter‐day assay was less than 15%. After a single oral administration of AA13 at the dose of 25 mg/kg, Cmax of AA13 was 1266.4 ± 316.1 ng/mL. AUC0–48 h was 6928.5 ± 1990.1 h·ng/mL, and t1/2 was 10.2 ± 0.8 h. Under intravenous administration of AA13 at a dosage of 250 μg/kg, AUC0–48 h was 785.7 ± 103.3 h⋅ng/mL, and t1/2 was 20.8 ± 7.2 h. Based on the results, oral bioavailability (F %) of AA13 in rats at 25 mg/kg was 8.82 %. [ABSTRACT FROM AUTHOR]

A recent virtual-lesion study using inhibitory repetitive transcranial magnetic stimulation (rTMS) confirmed the causal behavioral relevance of the precuneus in the evaluation of one's own memory performance (aka mnemonic metacognition). This study's goal is to elucidate how these TMS-induced neuromodulatory effects might relate to the neural correlates and be modulated by individual anatomical profiles in relation to meta-memory. In a within-subjects design, we assessed the impact of 20-min rTMS over the precuneus, compared to the vertex, across three magnetic resonance imaging (MRI) neuro-profiles on 18 healthy subjects during a memory versus a perceptual task. Task-based functional MRI revealed that BOLD signal magnitude in the precuneus is associated with variation in individual meta-memory efficiency. Moreover, individuals with higher resting-state functional connectivity (rs-fcMRI) between the precuneus and the hippocampus, or smaller gray matter volume in the stimulated precuneal region exhibit considerably higher vulnerability to the TMS effect. These effects were not observed in the perceptual domain. Thus, we provide compelling evidence in outlining a possible circuit encompassing the precuneus and its mnemonic midbrain neighbor the hippocampus at the service of realizing our meta-awareness during memory recollection of episodic details. Highlights: TMS disrupts the correlation between BOLD activity and meta-memory ability. TMS effect is modulated by rs-fcMRI between precuneus and hippocampus. Individuals with greater precuneal gray matter volume more immune to TMS effect. [ABSTRACT FROM AUTHOR]

Meta-aramid fibrid is prepared by precipitation, and aramid fibers are mixed with meta-aramid fibrid to make aramid paper by hot-pressing technology. Meta- -aramid fibrid possesses an excellent binding and adhesive properties with the aramid short fibers, yielding high mechanical properties of the aramid paper. The effects of hot-pressing temperature on the mechanical property of metaaramid paper are mainly discussed. Experimental results indicate that the mechanical property of aramid paper increases first and then decreases with the increase of hot-pressing temperature. The fundamental cause of this phenomenon is elucidated, and the aramid paper reaches its maximal mechanical property when the hot pressing temperature is 300 °C.. [ABSTRACT FROM AUTHOR]

Inverse-electron-demand Diels-Alder (iEDDA) reactions are an intriguing class of cycloaddition reactions that have attracted increasing attention for their application in bioorthogonal chemistry, the total synthesis of natural products, and materials science. In many cases, the application of the iEDDA reaction has been demonstrated as an innovative approach to achieve target structures. The theoretical aspects of this class of reactions are of particular interest for scientists as a means to understand the various factors, such as steric strain and electron density of the attached groups, that govern the reaction and thus to elucidate the reaction mechanism. This review aims to summarize both theoretical investigations and application-driven research work on the iEDDA reaction. First, the historical aspects and the theoretical basis of the reaction, especially recent advances in time-dependent density functional theory (TD-DFT) calculations, as well as catalysis strategies will be highlighted and discussed. Second, the applications of this novel reaction in the context of materials science, bioorthogonal chemistry, and total synthesis of natural products will be elaborated with selected recent examples. The challenges and opportunities of the iEDDA reaction will be highlighted to give more insight into its potential applications in many other research areas. [ABSTRACT FROM AUTHOR]

Lignin is one of the most promising applicable biomass resources, but its full utilization has yet to be realized, possibly, due to the difficulty in depolymerization and subsequent functionalization. We successfully carried out depolymerization of commercial Kraft lignin with the aid of formic acid and sodium formate to generate a mixture of monomeric and dimeric lignin. The obtained depolymerized lignin was further chemically modified by alkylation and subsequent esterification to afford lignin oil. The obtained lignin oil was thoroughly characterized by proton Nuclear Magnetic Resonance (H NMR) spectroscopy and Fourier Transform Infrared spectroscopy to validate its chemical nature. The properties of the lignin oil, including viscosity, total acid number and thermal properties were well characterized. The lignin oil was blended with commercial engine oil to examine their miscibility, and the result showed that it had good compatibility with some engine oil, rendering it as a potential lubricant or additive for low-end applications in industry. [ABSTRACT FROM AUTHOR]

Meta-aramid fibrid is a key material for aramid paper preparation. Its formation mechanism is elucidated and a mathematical model is established to reveal the main effects of coagulation properties and shear stress on the properties of aramid paper. [ABSTRACT FROM AUTHOR]

The electrochemical corrosion behavior in an open system of zirconium diboride (ZrB2) was studied in hydrofluoric acid aqueous solution at room temperature. Based on analysis of the intermediate products of corrosion, a corrosion mechanism for ZrB2 is suggested. The morphology evolution of anodic ZrB2 is investigated. The density of the hexagonal-pyramid grain array is dictated by current density, and the time dictates the length of the hexagonal pyramid grains. The microstructure of the surface can be controlled by the current density, which demonstrates that the surface wettability of ZrB2 can be modified by tailoring the current density. [ABSTRACT FROM AUTHOR]

A novel hard disk lubricant IDL2 was synthesised by reacting sodium 4-((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)phenoate with hexachlorocyclotriphosphazene, followed by treatment with 1H,1H-perfluoro-3,6,9-trioxatridecan-1-ol in the presence of sodium hydride and subsequent hydrolysis using sulfuric acid. The chemical structure of IDL2 was confirmed by proton nuclear magnetic resonance (1H NMR), phosphorus-31 (31P) NMR spectroscopy and mass spectrometer. The thermal property of IDL2 was analysed using thermal gravimetric analysis (TGA) and it shows better thermal stability than two commercial lubricants Z-DOL and Z-Tetraol with two and four terminal hydroxy groups, respectively. IDL2 was found to have comparable hydrophobicity to commercial lubricants Z-DOL, A20H and Z-Tetraol with water contact angles in the range of 78 - 85°, revealing that IDL2 has analogous surface energy to these commercial lubricants. IDL2 exhibits comparable friction coefficient to A20H and Z-Tetraol, but much lower than Z-DOL. More interestingly, it has a much high bonding ratio when compared with commonly used commercial lubricants under the same testing conditions due to the presence of two polar hydroxy groups, which enhance the interaction between lubricant and substrate. These promising properties of IDL2 show that it would be very potential for real application as a hard disk drive lubricant. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Mono-TPE modified POSS molecules, in which the flexible spacers between TPE and POSS moieties control their self-assembly and aggregation, exhibit a unique unadulterated monomer emission in organic solvents as well as an AIE emission in THF/water. [ABSTRACT FROM AUTHOR]

The research on electrochromic conjugated polymers (ECPs) and their devices has gone a long way. They can now perform with a multitude of color variations, high optical contrasts, rapid switching speeds and low power consumption. This review traces the progress of color control, synthetic methods, and the development of building blocks for ECPs. The advances in the integration and optimization of electrochromic devices (ECDs) in terms of their constituting components are presented. The potential of ECDs in numerous applications through the illustration of several prototypes is then highlighted. Finally, the challenges associated with the prospective commercialization of the said devices are discussed. [ABSTRACT FROM AUTHOR]

Organically modified cubic polyhedral oligomeric silsesquioxanes (POSS) have attracted increasing attention in the design of novel functional hybrid materials for applications such as porous materials, liquid crystals, semiconductors, high-temperature lubricants, fuel cells, and lithium batteries. The nanosized POSS moiety can be conveniently modified on the periphery with a variety of functional groups to lead to hybrid materials with desired functions. In addition, suitable mono-functionalized POSS derivatives can be incorporated into polymers as side chains via various synthetic strategies to offer a wide class of functional polymeric materials with tunable physical properties for targeted applications. In this Focus Review, we aim to summarize the recent developments on the chemistry and applications of POSS-based molecules and polymers. Moreover, the properties as well as assembly behavior of the POSS-based functional hybrid materials will be reviewed, and the relationship of the performance of the hybrid materials with the intrinsic nature of the POSS unit will be addressed. [ABSTRACT FROM AUTHOR]

The room-temperature synthesis of a new two-dimensional (2D) zirconium-containing carbide, Zr3C2Tz MXene is presented. In contrast to traditional preparation of MXene, the layered ternary Zr3Al3C5 material instead of MAX phases is used as source under hydrofluoric acid treatment. The structural, mechanical, and electronic properties of the synthesized 2D carbide are investigated, combined with first-principles density functional calculations. A comparative study on the structrual stability of our obtained 2D Zr3C2Tz and Ti3C2Tz MXenes at elevated temperatures is performed. The obtained 2D Zr3C2Tz exhibits relatively better ability to maintain 2D nature and strucural integrity compared to Ti-based Mxene. The difference in structural stability under high temperature condition is explained by a theoretical investigation on binding energy. [ABSTRACT FROM AUTHOR]

The room-temperature synthesis of a new two-dimensional (2D) zirconium-containing carbide, Zr3C2Tz MXene is presented. In contrast to traditional preparation of MXene, the layered ternary Zr3Al3C5 material instead of MAX phases is used as source under hydrofluoric acid treatment. The structural, mechanical, and electronic properties of the synthesized 2D carbide are investigated, combined with first-principles density functional calculations. A comparative study on the structrual stability of our obtained 2D Zr3C2Tz and Ti3C2Tz MXenes at elevated temperatures is performed. The obtained 2D Zr3C2Tz exhibits relatively better ability to maintain 2D nature and strucural integrity compared to Ti-based Mxene. The difference in structural stability under high temperature condition is explained by a theoretical investigation on binding energy. [ABSTRACT FROM AUTHOR]

To widen the application of nanofibers web in the field of medical health materials, a new Ag/amino-terminated hyperbranched polymer (HBP)/polyacrylonitrile (PAN) nanofiber web with excellent antimicrobial activity and filtration property was produced with Ag/HBP dispersion solution and PAN nanofiber. Ag/HBP dispersion solution was prepared with HBP as reducer and stabilizer, and Ag/HBP/PAN nanofiber was prepared by modifying electrospun PAN nanofiber with Ag/HBP aqueous solution. The characterization results showed that spherical Ag nanoparticles were prepared and they had a narrow distribution in HBP aqueous solution. The results of Ag/HBP/PAN nanofiber characterized with SEM and EDS showed that the content of silver nanoparticles on the surface of PAN nanofiber was on the increase when the treating temperature rose. The bacterial reduction rates of HBP-treated PAN nanofiber against S. aureus and E. coli were about 89%, while those of the Ag/HBP/PAN nanofiber against S. aureus and E. coli were 99.9% and 99.96%, respectively, due to the cooperative effects from the amino groups in HBP and Ag nanoparticles. Moreover, the small pores and high porosity in Ag/HBP/PAN nanofiber web resulted in high filtration efficiency (99.9%) for removing smaller particles (0.1 μm~0.7 μm), which was much higher than that of the gauze mask. [ABSTRACT FROM AUTHOR]

A microporous hydrogen-bonded organic framework (HOF) derived from a polyhedral oligomeric silsesquioxane (POSS) intermediate and an aggregation-induced emission (AIE) luminogen tetraphenylethene (TPE) derivative has been synthesized and structurally characterized by various methods. This unique HOF exhibits a permanent porosity with a Brunauer–Emmett–Teller (BET) surface area of 101.9 m2 g−1. This HOF could be well dispersed in organic solvents in the form of nanoparticles with a size of a few hundred nanometers. These nanoparticles are highly fluorescent in organic solution, and exhibit a high fluorescence quenching selectivity towards copper ions. Furthermore, the fluorescence of this HOF could be recovered by the removal of copper ions upon addition of cyanide and, more interestingly, this process could be repeated several times without considerably sacrificing the sensing activity towards copper ions. [ABSTRACT FROM AUTHOR]

Fast and highly efficient intramolecular singlet exciton fission in a pentacene dimer, consisting of two covalently attached, nearly orthogonal pentacene units is reported. Fission to triplet excitons from this ground state geometry occurs within 1 ps in isolated molecules in solution and dispersed solid matrices. The process exhibits a sensitivity to environmental polarity and competes with geometric relaxation in the singlet state, while subsequent triplet decay is strongly dependent on conformational freedom. The near orthogonal arrangement of the pentacene units is unlike any structure currently proposed for efficient singlet exciton fission and may lead to new molecular design rules. [ABSTRACT FROM AUTHOR]

A series of 4,9-dihydro- s-indaceno[1,2-b:5,6-b′]dithiophene-based conjugated polymers with 3,4-bis(dodecyloxy)thiophene, 3,3-bis((dodecyloxy)methyl)-3,4-dihydro-2 H-thieno[3,4- b] [, ] dioxepine and 3,4-ethylenedioxythiophene as co-monomers were synthesized via Stille coupling reaction in more than 50 % yields. These polymers possess relatively high number-average molecular weights of 14,900-21,000 g mol and exhibit good solubility in common organic solvents. The physical and electrochemical properties of these polymers were studied, and the polymers showed optical bandgap between 2.04 and 2.08 eV. Electrochromic devices showed a rare and reversible colour change between dark red at neutral state and black at oxidized state with optical switching contrast ratios of up to 50 % at λ and 90 % at 1500 nm in the visible and NIR regions, respectively. Graphical abstract: 4,9-dihydro- s-indaceno[1,2-b:5,6-b']dithiophene-based conjugated polymers showing rare and reversible colour change between dark red at neutral state and black at oxidized state were synthesized via Stille coupling. These polymers possess high optical contrast in both the visible and NIR regions.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A series of dithienothiophene-based electrochromic polymers are synthesized by a Stille coupling reaction of 2,6-bis(trimethylstannyl)dithieno[3,2- b:2′,3′- d]thiophene, 2,5-dibromo-3,4-bis(dodecyloxy)thiophene, and tris(4-bromophenylamine). The resulting polymers have high molecular weights in the range of 59 200 to 81 300 g mol−1, and good solubility in common organic solvents. The polymer films are purple/red in neutral states and gradually become gray when oxidized to an intermediate state and blue when fully oxidized. Incorporation of triphenylamine into the polymer chains has resulted in a significant increase in the redox stability, which renders this a potential method to create high-performance electrochromic polymers. [ABSTRACT FROM AUTHOR]

Aggregation induced emission (AIE) active copolymers P1–P6 with high molecular weights (14 000–17 000) and low polydispersity indices (1.3–1.4) were prepared through copolymerization of N-isopropyl acrylamide (NIPAM) and tetra(phenyl)ethene (TPE)-based acrylate monomers. Copolymers P1–P6 show comparable thermal stability to poly(N-isopropylacrylamide) (PNIPAM), while their glass transition temperatures are higher by 7–9 °C than those of pristine PNIPAM. Copolymers P1–P6 are soluble in common organic solvents as well as in water. They retain a similar thermal sensitivity to PNIPAM, but their lower critical solution temperatures (LCST) are reduced with increase of TPE content. By changing the molar ratio of P1–P6/poly(methacrylic acid) (PMAA) and pH, complexes P1–P6–PMMA were studied by fluorescence spectroscopy and dynamic light scattering (DLS). The complexes are non-emissive in THF, and their fluorescence can be turned on upon addition of water. Moreover, their fluorescence is enhanced with the decrease in pH values due to the formation of interpenetrating polymer networks (IPNs) through inter-polymer hydrogen bonding. Fluorescence spectroscopy and DLS results also reveal that the phase transition behaviour of IPNs upon heating could be significantly modified by pH change. Reduction in the pH value from 7.0 to 4.0 leads to the decrease in LSCT of IPNs by up to 5 °C with respect to PNIPAM. By tuning the pH value to dissociate the formed inter-polymer hydrogen bonds, the formed IPNs would be able to fold cooperatively to a compact structure without a loss of solubility at temperatures below the LCST. Thus, these novel IPNs with AIE active moieties would be used as drug delivery systems, in which the release process could be readily monitored by fluorescence spectroscopy. [ABSTRACT FROM AUTHOR]

ABSTRACT Donor-acceptor type polymers bearing diketopyrrolopyrrole and 3,4-ethylenedioxythiophene units are reported. The polymers are green and exhibit very low band-gaps (1.19 eV) with strong and broad absorption (maxima of about 830 nm) in the near infrared (NIR) region in their neutral film states. The polymers display color changes between dark green and light blue with exceptional optical contrasts in the NIR regions of up to 78 and 63% as thin films and single-layer electrochromic devices, respectively. Fast switching, good stabilities as well as high coloration efficiencies (743-901 cm2 C−1) were also observed. The polymers could also be potentially used as photovoltaic material, with a power conversion efficiency of up to 1.68%. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1287-1295 [ABSTRACT FROM AUTHOR]

This study reports a viable method for the synthesis of Ti2SC phase using iron disulfide or iron sulfide as sulfur source and a post-treatment with acid. The reaction routes to Ti2SC phases starting from two different chemical compositions of 2Ti-FeS2-2TiC and Ti-FeS-TiC were in detail explored and compared through the analysis of X-ray diffraction, thermogravimetry/differential scanning calorimetry, and scanning electron microscopy results. Unlike the Ti-FeS-TiC composition, the reaction route from 2Ti-FeS2-2TiC composition contained an extra decomposition step in which FeS2 transformed to activated FeS and released molecular state sulfur at temperature around 500°C. The latter at this temperature could successfully trigger the reaction of Ti-S-TiC to form Ti2SC phase, which was an analogous self-propagating high-temperature synthesis with a high transient temperature. On the contrary, only trace of Ti2SC phase could be obtained at temperature as high as 1200°C from the Ti-FeS-TiC composition. The main impurity phases from these iron disulfide reactant systems were Fe and FeS, and they could be easily purified by dissolution in H2SO4 solution, which resulted in Ti2SC phase with a minor TiC phase in the final product. [ABSTRACT FROM AUTHOR]

Ocarboxymethyl chitosan (OCMC) was synthesized by ultrasonic irradiation with chitosan and chloroace-tic acid in NaOH-ethanol. The degree of substitution (DS) of carboxymethyl and amino retained amount (NH2%) were studied under the orthogonal experiments of four factors at three different levels and the reaction condition was optimized Then quaternary ammonium group was introduced by the reaction of preferable OCMC with glycidyl tri-methylammonium (GX\) in ethanol. The DS of the quatemization group was studied. Antimicrobial activities of quatemized Ocarboxymethyl chitosan (Q(X)MC) were evaluated against Escherichia coli and Staphylococcus au-reus. The structures of the derivatives are characterized by FTIR spectrometer and SEM. The lowest antibacterial concentrations of (30CMC is 8 times lower than that of (XMC. Experiment results validated that QCXMC is better than (XMC in the properties of antimicrobial activity. [ABSTRACT FROM AUTHOR]

Rheological characteristics of fiber-modified asphalt mixture were investigated. Cellulous fiber, polyester fiber and mineral fiber were used as additives for asphalt mixture, and the dosages were 0.3%, 0.3%, 0.4%, respectively. Dynamic modulus test using superpave simple performance tester (SPT) was adopted to study the dynamic modulus and phase angle for the control mixture and fiber-modified ones at various temperatures and frequencies. Test results show that the rheological properties can be improved significantly by the addition of various fibers. The dynamic modulus increases with the increase of frequency, and the phase angle decreases with the increase of frequency. When various fibers are used, the dynamic modulus increases and phase angle decreases at each frequency. This indicates that the stiffness and the elastic portion of fiber-modified asphalt mixtures can be enhanced when various fibers are used, which results in the change of viscoelastic properties of mixtures. The creep test results show that the total strain and the permanent strain of asphalt mixtures during load-unload cycle can be significantly reduced, which results in the improvement of resistance to permanent deformation for asphalt mixtures containing various fiber additives. The Burgers model can be employed effectively to illustrate the rheological properties of fiber modified asphalt mixtures. [ABSTRACT FROM AUTHOR]

Hymexazol (3-Hydroxy-5-methylisoxazole) as the main ingredients of HI (elicitor) was used to screen salt-tolerant species from 122 salt-tolerant rice ( Oryza sativa L.) cultivars under specific inducement. The results showed that the local species R6 is highly induce-sensitive. R6 showed salt tolerance during the whole growth period by using 1.0% NaCl solution after HI treatment. Cyclosporin A (CsA) and verapamil (VP) as P-glycoprotein (PGP) inhibitors and rifampin (RFP) as a PGP elicitor were used to treat R6. The morphological traits, structure of the root, physiological characteristics of leaf and root systems, the content of endogenous hormones indole-3-acetic acid (IAA) and abscisic acid (ABA) etc. show that CsA, VP and RFP had remarkable effects on the rice's salt tolerance. Hymexazol inducement (HI) can improve the rice's salt tolerance greatly and make it more salt-resistant. (Handling editor: Jin-Zhong Cui) [ABSTRACT FROM AUTHOR]

The aqueous phase oxidation of gaseous elemental mercury (Hg0) by potassium persulfate (KPS) catalyzed by Ag+ was investigated using a glass bubble column reactor. Concentration of gaseous mercury and potassium persulfate were measured by cold vapor atom absorption (CVAA) and ion chromatograph (IC), respectively. The effects of pH value, concentration of potassium persulfate and silver nitrate (SN), temperature, Hg0 concentration in the reactor inlet and tertiary butanol (TBA), free radical scavenger, on the removal efficiency of Hg0 were studied. The results showed that the removal efficiency of Hg0 increased with increasing concentration of potassium persulfate and silver nitrate, while temperature and TBA were negatively effective. Furthermore, the removal efficiency of Hg0 was much better in neutral solution than in both acidic and alkaline solution. But the influence of pH was almost eliminated by adding AgNO3. High Hg0 concentration has positive effect. The possible reaction mechanism of gaseous mercury was also discussed. [ABSTRACT FROM AUTHOR]