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The high integration density of microelectronic devices leads to local heat accumulation, and effective heat dissipation and signal transmission of packaging materials have become the primary issues to be solved. However, existing polymer materials have difficulty meeting the requirements due to their unsatisfactory thermal conductivity and thermal expansion properties. In this work, we proposed the use of digital light processing (DLP) printing technology to construct a triply periodic minimum surface (TPMS) skeleton, and a continuous and efficient heat conduction path was successfully constructed in epoxy resin by impregnating h-BN on the skeleton surface. When the loading of h-BN was 20 vol%, the thermal conductivity of the TPMS(SiO 2)@BN/EP(BN) composites was 1.86 W/(m·K), which was 786 % higher than that of pure epoxy resin. In addition, the thermal expansion coefficient of the composites decreased by more than 70 %. At the test frequencies of 3∼10 MHz, the composites showed stable dielectric properties, and the dielectric constant was always maintained in a low range, between 3.85 and 4.15. This work has realized the transformation of the method for constructing a heat conduction path from disordered to ordered and from random to repeatable. This provides a new strategy for the selection of microelectronic packaging materials. [ABSTRACT FROM AUTHOR]

A multicolour LED is a miniaturized, long-lasting, and easy-to-achieve colour adjustable emission light source. It is widely used in outdoor displays and room lighting fields. However, the increase in the cost and the decrease in luminous efficiency when adjusting lighting colours have constrained the development of multicolour LEDs. In this study, we initially designed a phosphor conversion pixel array through optical simulation and then prepared the phosphor conversion pixel arrays with different layouts using a semi-cured template method. Finally, we packaged the phosphor conversion pixel array with the blue LED array as a remote phosphor LED. The measurement of the luminous performance indicated that the colour gamut of multicolour LEDs was included in the simulated colour gamut, and the colour of the light was consistent with the design guidelines. Notably, the multicolour LED emission efficiency packaged with a phosphor conversion pixel array could reach 125 lm/W, and the hexagonal phosphor conversion pixel array had better emission performance than the square phosphor conversion pixel array. • Based on the Monte Carlo principle, multicolour LEDs composed of array phosphor-converted film and blue-LED chip are designed. • Phosphor-converted pixel arrays are prepared by semi-cured template method with high moulding quality. • By comparing the experimental and simulation results, colour-tuneable characteristics of the multicolour LEDs is verified. • The luminous efficiency of multicolour LEDs reach up to 125.0 lm/W and changing pixel can reduce the secondary reabsorption of fluorescence. [ABSTRACT FROM AUTHOR]

The P2Y 14 receptor (P2Y 14 R), a G protein-coupled receptor (GPCR), is activated by extracellular nucleotides. P2Y 14 R is involved in inflammatory, diabetes, immune processes and other related complications, and is therefore an attractive therapeutic target. As the three-dimensional structure of the P2Y 14 R has not yet been elucidated, homology modeling based on the crystallography of the closely related P2Y 12 R have been used in the structure-based design of P2Y 14 R ligands. Several P2Y 14 R antagonists with excellent potency and high subtype-selectivity have been discovered in recent years. In this review, development of novel small molecules as antagonists of P2Y 14 R was described. UDP non-competitive P2Y 14 R antagonist. UDP competitive P2Y 14 R antagonists. Image 1 • Development of novel small molecules as antagonists of P2Y 14 R was reviewed. • Developing drug-like UDP competitive P2Y 14 R antagonists was mentioned. • UDP non-competitive P2Y 14 R antagonist avoiding side-effects was suggested. [ABSTRACT FROM AUTHOR]

A three dimensional (3D) reduced graphene oxide (rGO)/zeolitic imidazolate framework-67(ZIF-67) aerogel (3D rGO/ZIF-67 aerogel) was prepared via in situ assembly of ZIF-67 polyhedrons on a 3D rGO networks, not only providing multifarious affinity interactions for synergistic promoting the adsorption behavior of organic dyes, but also constructing a holder for ZIF-67 polyhedrons to convenient separation. This porous aerogel displays excellent absorption ability for cationic dyes (crystal violet, CV) and anionic dyes (methyl orange, MO). The maximum adsorption capacities are up to 1714.2 mg·g −1 and 426.3 mg·g −1 for CV and MO, respectively. 3D rGO/ZIF-67 aerogel shows a remarkable promoting of CV adsorption capacity than pure 3D rGO and ZIF-67. The ultrahigh adsorption capability towards cationic CV dyes is mainly driven by π-π interactions and electrostatic interactions between 3D rGO/ZIF-67 aerogel and dye molecules, and synergistic interactions at the interface of 3D rGO and ZIF-67 polyhedrons. The high adsorption capability towards anionic MO dyes is mainly due to the porosity of ZIF-67 polyhedrons and electrostatic attraction between MO and ZIF-67. The multi-component property of 3D rGO/ZIF-67 aerogel shows a great potential application in dye-bearing wastewater treatment. [ABSTRACT FROM AUTHOR]

Three linear push-pull compounds comprised of difluoroboron β-diketonate and triphenylamine unit 4,6-Bis(4-(diphenylamino)phenyl)-2,2-difluoro-2H-1,3,2-dioxaborinin-1-ium-2-uide, (E)-6-(4-(Diphenylamino)phenyl)-4(4(diphenylamino)styryl)-2,2-difluoro-2H-1,3,2-dioxaborinin-1ium-2-uide and 4,6-Bis((E)-4-(diphenylamino)styryl)-2,2-difluoro-2H-1,3,2-dioxaborinin-1-ium-2-uide (ABA, ABVA, and AVBVA) have been probed by many spectroscopies. The results clarify the photo-physical property of the compounds where ABVA and AVBVA are linked with vinyl units (V). The solvent-dependent steady absorption and photoluminescence spectra data shows that the vinyl unit and the polarity of the solvent influence the photo-physical properties of the compound. Moreover, the vinyl unit would further enhance the role of the polar environment. The transient absorption measurement then offers excitation relaxation behavior. The results show that excited compounds in cyclohexene go back to the ground state through the intramolecular charge transfer (ICT) state, and the transfer lifetime from the initial excited state to the ICT state would prolong after the introduction of vinyl unit. The relaxation behavior becomes complex when cyclohexene is replaced by tetrahydrofuran. Some excited compounds go directly back to the ground state and others go back to the ground state after passing through the ICT state. In addition, two-photon PL measurements and a Z-scan technique are employed, and this confirms that these compounds have two-photon behavior, but the two-photon absorption section gradually decreases. This decrease is attributed to the spectral shifting affected by the vinyl unit. [ABSTRACT FROM AUTHOR]

Through comparing the linear and nonlinear optical property of two pull-push chromophores, which are composed of difluoroboron β-diketonate functionalized with carbazole and tert-butyl carbazole, the role of tert-butyl in chromosphere has been discussed in detail. The tert-butyl unit would lead to the absorption and fluorescence peak red shift and accelerate the fluorescence relaxation rate of chromophores. Moreover, the tert-butyl unit would affect obviously the two-photon optical property of chromophore according to the Z-scan test. The transient absorption (TA) data shows that these two pull-push chromopphores both own intramolecular charge transfer (ICT) characteristics and the tert-butyl unit accelerate the dynamic rate of ICT generation and relaxation process, which may be responsible for the variance of fluorescence property. [ABSTRACT FROM AUTHOR]

The design and preparation of hierarchical porous transition metal oxide-carbon matrix anodes with unique structure play the significant role in highly reversible lithium ion batteries. Herein, hierarchical porous wheat-like Co 3 O 4 on carbon derived from natural silk (named as SK@Co 3 O 4) nanobelts are fabricated successfully by one-step hydrothermal technique and ensuing high-temperature calcination. The wheat-like SK@Co 3 O 4 nanobelts consist of a number of nanobeams. The length of nanobelts is around 1 µm whereas the diameter is 200 nm. Moreover, the SK@Co 3 O 4 anode for lithium ion batteries retains 1108 mA h g−1 following 100 cycles at 100 mA g−1, 707 mA h g−1 and 709 mA h g−1 after 150 cycles at 2 A g−1, 625 mA h g−1 and 617 mA h g−1 after 150 cycles at 5 A g−1,which show extraordinary cycle stability of the composite. The remarkable lithium storage property results from the hierarchical porous structure and this structure can not only provide a short ion transport path but also raise the area of contact between the electrolyte and electrode. [Display omitted] • Wheat-like Co 3 O 4 on carbon derived from silk was synthesized. • Silk was used as carbon source. • SK@Co 3 O 4 nanobelts showed high lithium storage performance. [ABSTRACT FROM AUTHOR]

The pyrolysis of biomass was conducted using a microwave heating system operated at 2.45 GHz. Additives, such as silica carbon, activated carbon, coke produced through microwave-assisted pyrolysis, potassium carbonate, and sodium hydrate, were investigated for their effects on the sawdust pyrolysis. It was found that additives had significant effects on the yields and properties of the final products. By employing silica carbon, the gas and liquid yields were relatively low, due to the non-uniform mixing caused by big density difference between the sawdust and silica carbon particles. However, with potassium carbonate and sodium hydrate, the pyrolysis products are mainly gases, since both additives can absorb microwave strongly, making extremely high temperature inside the sawdust. The liquid products were analyzed by electrospray FT–ICR MS. Potassium carbonate can simplify the bio-oil composition and reduce compound types, which is beneficial to its further applications. The pyrolysis is highly influenced by heating rate and a first order was found for the reaction. Additives under microwave irradiation would enhance the heating rate, while they mainly act as catalysts instead of enhanced heating. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fatty acid- and terpene-derived biofuels are ideal advanced transportation fuels. • Y. lipolytica is a valuable chassis for the overproduction of advanced biofuels. • Engineering Y. lipolytica to overproduce advanced biofuels is urgently needed. • Engineering strategies in Y. lipolytica for advanced biofuel overproduction are summarized. • Future perspectives in Y. lipolytica advanced biofuel production are prospected. Energy security and global climate change have necessitated the development of renewable energy with net-zero emissions. As alternatives to traditional fuels used in heavy-duty vehicles, advanced biofuels derived from fatty acids and terpenes have similar properties to current petroleum-based fuels, which makes them compatible with existing storage and transportation infrastructures. The fast development of metabolic engineering and synthetic biology has shown that microorganisms can be engineered to convert renewable feedstocks into these advanced biofuels. The oleaginous yeast Yarrowia lipolytica is rapidly emerging as a valuable chassis for the sustainable production of advanced biofuels derived from fatty acids and terpenes. Here, we provide a summary of the strategies developed in recent years for engineering Y. lipolytica to synthesize advanced biofuels. Finally, efficient biotechnological strategies for the production of these advanced biofuels and perspectives for future research are also discussed. [ABSTRACT FROM AUTHOR]

A Cu-coated Al 2 O 3 substrates which can be used for power modules are prepared via sintering and reduction of CuO–SiO 2 film onto the surface of Al 2 O 3 ceramic without precious metal brazing filler or high-vacuum equipment. This method has a significant cost advantage over the existing technology. Effects of oxygen partial pressure from sintering atmosphere and SiO 2 content on microstructure and mechanical properties of Cu/Al 2 O 3 interface are systematically investigated. Phase compositions and morphologies of sintered Cu 2 O layer, reduced Cu layer and reactive layer are characterized via X-ray diffraction and scanning electron microscopy. In addition, physicochemical changes within CuO–SiO 2 during sintering are characterized by thermogravimetry-differential scanning calorimeter. It is found that oxygen and SiO 2 can promote the generation of Cu 2 O–CuO–SiO 2 eutectic phase with low melting point upon sintering, which increases the thickness of reaction layer and the densification of Cu layer. The shear strength between the Cu layer and the Al 2 O 3 substrate is enhanced with the increase in Cu layer densification degree, while varying in irregular manner with the thickness of reaction layer. In particular, the highest shear strength of 62.70 MPa is obtained at oxygen partial pressure of 0.02 atm and SiO 2 content of 1.5 wt%. [ABSTRACT FROM AUTHOR]

P2Y 14 nucleotide receptor plays important roles in series of physiological and pathologic events especially associated with immune and inflammation. Based on the 3-amide benzoic acid scaffold reported by our group previously, a series of 5-aryl-3-amide benzoic acid derivatives were designed as novel P2Y 14 antagonists with improved pharmacokinetic properties. Among which compound 11m showed most potent P2Y 14 antagonizing activity with an IC 50 value of 2.18 nM, furnishing greatly improved water solubility and bioavailability compared with PPTN. In MSU-induced acute gouty arthritis model in mice, 11m exerted promising in vivo efficacy in alleviating mice paw swelling and inflammatory infiltration. Mechanistically, compound 11m notably blocked pyroptosis of macrophages through inhibiting NLRP3 inflammasome activation. This work may contribute to the identification of potential therapeutic agents to intervene in acute gouty arthritis. [Display omitted] • A series of 3-amide-5-aryl benzoic acids was identified as novel P2Y 14 R antagonists. • Compound 11m demonstrated greatly improved aqueous solubility and excellent pharmacokinetic properties. • Compound 11m showed potent anti-inflammatory effect in vivo. [ABSTRACT FROM AUTHOR]

We have synthesized two new two-photon active dendritic molecules with tetraphenylmethane core with four phenothiazine-based arms. They show good solubility in organic solvents, including dichloromethane, chloroform, toluene and tetrahydrofuran. It is found that the two dendrimers display strong two-photon absorption and two-photon excited up-conversion fluorescence at 800 nm. • Two new phenothiazine-based dendrimers with tetraphenylmethane cores have been synthesized. • The dendritic molecules display two-photon absorption activity. • The two-photon absorption cross section increased with the increasing of the conjugation degree. [ABSTRACT FROM AUTHOR]

Cell fusion is a fundamental biological process that is involved in the development of most eukaryotic organisms. During the fusion process in Saccharomyces cerevisiae , cells respond to pheromones to trigger the MAPK (mitogen-activated protein kinase) cascade to initiate mating, followed by polarization, cell-wall remodeling, membrane fusion, and karyogamy. We highlight the applications of the yeast mating signal pathway in promoter engineering for tuning the expression of output genes, as well as in metabolic engineering for decoupling growth and metabolism, biosensors for sensitive detection and signal amplification, genetic circuits for programmable biological functionalities, and artificial consortia for cell–cell communication. Strategies such as exploiting rational engineering of modular circuits and optimizing the reproductive pathway to precisely maneuver physiological events have implications for scientific research and industrial development. The mating response of yeast gives deep insights that facilitate the application of cell fusion to gene transfer, antibody production, and cell reprogramming. Components of the yeast mating-specific mitogen-activated protein kinase (MAPK) signaling pathway, including scaffolds, G protein-coupled receptors (GPCRs), and pheromone-responsive promoters, constitute a toolbox for the rational design of artificial systems. The yeast mating signal pathway has significant synthetic biology applications, including tuning the outputs by promoter engineering, decoupling growth and metabolism through metabolic engineering, detecting and amplifying signals in biosensors, programming biological functions in circuits, and manipulating cell–cell communication in artificial consortia. Advances in synthetic biology tools such as omics, microfluidics, CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9), and machine learning have significantly boosted cell-fusion studies. [ABSTRACT FROM AUTHOR]

The removal of organic contaminants from water poses a significant challenge that can be tackled by integrating adsorption and photocatalytic degradation functions in a single architecture. However, traditional powdery nanomaterials face challenges in separation and lack synergistic function, hampering their practical application. This study presents a one-step hydrothermal synthesis of a convenient recyclable Bi 2 O 2.33 /Bi 2 O 3 @ECNF (electrospun carbon nanofibers), which combines both adsorption and photocatalytic performance. The Bi 2 O 2.33 /Bi 2 O 3 exhibits high adsorption removal of methyl orange (MO), reaching 94.56 % and a maximum capacity of 213.13 mg g−1. Additionally, the Bi 2 O 2.33 /Bi 2 O 3 shows a high charge transfer rate, strong redox ability, and efficient removal of Rhodamine B (RhB) at 83.01 %. Loading the Bi 2 O 2.33 /Bi 2 O 3 on lightweight carbon fibers allows for easy recycling. The Bi 2 O 2.33 /Bi 2 O 3 @ECNF demonstrates excellent stability and reusability, with a removal rate of 87.37 % for tetracycline hydrochloride (TCH) at high concentrations. This work presents a promising solution for the practical application of photocatalysts by overcoming the limitations of single photocatalysts and minimizing secondary pollution from single adsorbents. [Display omitted] [ABSTRACT FROM AUTHOR]

Regeneration serves as a self-protective mechanism that allows a tissue or organ to recover its entire form and function after suffering damage. However, the regenerative capacity varies greatly within the plant kingdom. Primitive plants frequently display an amazing regenerative ability as they have developed a complex system and strategy for long-term survival under extreme stress conditions. The regenerative ability of dicot species is highly variable, but that of monocots often exhibits extreme recalcitrance to tissue replenishment. Recent studies have revealed key factors and signals that affect cell fate during plant regeneration, some of which are conserved among the plant lineage. Among these, several members of the ETHYLENE RESPONSE FACTOR (ERF) transcription factors have been implicated in wound signaling, playing crucial roles in the regenerative mechanisms after different types of wounding. An understanding of plant regeneration may ultimately lead to an increased regenerative potential of recalcitrant species, producing more high-yielding, multi-resistant and environmentally friendly crops and ensuring the long-term development of global agriculture. [ABSTRACT FROM AUTHOR]

New dimesitylborylthiophene derivative with terminal tetraphenylethene TPETB has been synthesized. It was found that TPETB exhibited aggregation-induced emission behavior and reversible mechanofluorochromism. For instance, the emission intensity of TPETB in THF/H 2 O with water fraction of 90% was ca. 21 times higher than that in THF. In addition, grinding the as-prepared crystal of TPETB the emitting color changed from sky blue to yellowish green. Meanwhile, the ground powder could recover to crystalline structure with sky blue emission when it was exposed to CH 2 Cl 2 vapor. It was suggested that the transformation between crystalline and amorphous states led to the changes of solid emitting colors in response to external mechanical forces. It should be noted that TPETB could detect F − selectively, and the detection limit was 1.67 × 10 −8 mol/L in CH 2 Cl 2 . [ABSTRACT FROM AUTHOR]

• PELP1 was upregulated during PDLSCs osteogenic differentiation. • Runx2 expression and ERK phosphorylation were controlled by PELP1 in PDLSCs. • ERK inhibition restrained PELP1 induced Runx2 expression in PDLSCs. The aim of this study was to determine the physiological function and mechanism of proline-, glutamic acid-, and leucine-rich protein 1 (PELP1) in the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) at the molecular level in vitro. During the osteogenic differentiation of hPDLSCs, the change of PELP1 and the osteogenic commitment markers runt-related transcription factor 2(RUNX2), alkaline phosphatase (ALP) and osteocalcin (OCN) were monitored by quantitative real-time PCR (qRT-PCR) and western blots. To elucidate how PELP1 regulates RUNX2 , the expression of RUNX2 , the phosphorylation of extracellular regulated protein kinases (ERK) and subcellular location of PELP1 were detected under conditions that PELP1 was either knockdown by specific siRNA or overexpressed. A pharmacological inhibitor of ERK, U0126 was used while PELP1 was overexpressed, and the expression of RUNX2 was monitored by qRT-PCR. PELP1 was upregulated during the osteogenic differentiation of hPDLSCs. Knockdown of PELP1 suppressed the expression of RUNX2 , whereas overexpression of PELP1 increased RUNX2 expression. Moreover, PELP1 knockdown resulted in reduced ERK phosphorylation and RUNX2 expression, and PELP1 overexpression induced RUNX2 expression was inhibited by U0126 in the hPDLSCs. PELP1 regulates the expression of RUNX2 during the osteogenic differentiation of hPDLSCs and that the ERK pathway is involved in this process. [ABSTRACT FROM AUTHOR]

• Superhydrophilic nanostructure was fabricated for improving soft tissue sealing. • The properties of the surface regulate the behavior of human gingival fibroblasts. • FAK/integrin-mediated adhesion seemed to be induced by the hydrogenated surface. Soft tissue integration is critical for the long-term retention of dental implants. The surface properties including topography and wettability can impact soft tissue sealing. In our work, a thermal hydrogenation technique was applied to modify anodized titanium dioxide nanotubes (TNTs). However, the effects of the hydrogenated surface on soft-tissue cells remain unclear. The aim of the present study was to investigate the bioactivities of human gingival fibroblasts (HGFs) on structured surfaces, which determine the early formation of soft tissue sealing. Three groups were examined: commercially pure titanium (Ti), anodized TNTs (air-TNTs) and hydrogenated TNTs (H 2 -TNTs). Scanning electron microscopy showed the nanotubular topography on the titanium surfaces after anodization. Then, hydrogenation ensured that the H 2 -TNTs were superhydrophilic with a contact angle of 3.5 ± 0.8°. In vitro studies such as cell adhesion assays, cell morphology, immunocytochemistry, wound healing assays, real-time PCR and enzyme-linked immunosorbent assays displayed enhanced adhesion, migration, relative gene expression levels, and extracellular matrix synthesis of the HGFs on H 2 -TNTs. Interestingly, focal adhesion kinase activation and integrin-mediated adhesion seemed to be induced by the H 2 -TNT surface. Our results revealed that a superhydrophilic nanostructure modified by anodization and hydrogenation can improve the bioactivity of HGFs and connective tissue regeneration, which will further promote and expand the application of titanium dioxide nanotubes in dental implants. [ABSTRACT FROM AUTHOR]

The development of the economy and society makes heavy metals (HMs) pollution more and more serious. And, pollution source identification is the primary work of environmental pollution control and land planning. Notably, stable isotope technology has a high ability to distinguish pollution sources, and can better reflect the migration behavior and contribution of HMs from diverse sources, which has become a hot research tool for pollution source identification of HMs. Currently, the rapid development of isotope analysis technology provides a relatively reliable reference for pollution tracking. Based on this background, the fractionation mechanism of stable isotopes and the influence of environmental processes on isotope fractionation are reviewed. Furthermore, the processes and requirements for the measurement of metal stable isotope ratios are summarized, and the calibration methods and detection accuracy of sample measurement are evaluated. Besides, the current commonly used binary model and multi-mixed models in the identification of contaminant sources are also concluded. Moreover, the isotopic changes of different metallic elements under natural and anthropogenic conditions are discussed in detail, and the application prospects of multi-isotope coupling in the traceability of environmental geochemistry are evaluated. This work has some guidance for the application of stable isotopes in the source identification of environmental pollution. [Display omitted] • The mechanism of isotopic fractionation needs to be further investigated. • Isotopic techniques have limitations in terms of source contribution calculation. • The overlap of isotopic compositions reduces the accuracy of identification results. • Isotopic techniques are able to identify the sources of HMs in different media. • Combining multiple isotopes could improve the accuracy of traceability results. [ABSTRACT FROM AUTHOR]

Removing noxious dyes and detecting excessive metal ions in water are both effective means to prevent damage from contaminants and ensure water safety. The emphasis problems were addressed by preparation a polyacrylamide chitosan (PAAM/CS) hydrogel. Polyacrylamide (PAAM) provides overall mechanical strength to carry loads and facilitate circulation, chitosan (CS) provides adsorption positions with high adsorption capacity. Which made that PAMM/CS hydrogel efficiently performed sorption of xylenol orange (XO). As the functional dye, XO binds to PAAM/CS and confers colorimetric properties on PAAM/CS hydrogels. XO sorbed hydrogel realized fluorescence dual-signal detection of Fe3+ and Al3+ in water. The significant swelling and adsorption potency of the hydrogel, combined with the dual-signal detection capability of XO sorbed hydrogel, make this hydrogel a versatile material for environmental applications. • Polyacrylamide chitosan hydrogel was prepared as adsorbent. • Adsorption mechanism is mainly based on electrostatic attraction. • After five adsorption cycles, the composite hydrogel still achieved 83.29 % removal of xylenol orange. • XO sorbed hydrogel realized fluorescence dual-signal detection of Fe3+ and Al3+ in water. [ABSTRACT FROM AUTHOR]

Food safety is one of the greatest public health challenges. Developing ultrasensitive detection methods for analytes at ultra-trace levels is, therefore, essential. In recent years, the bio-barcode assay (BCA) has emerged as an effective ultrasensitive detection strategy that is based on the indirect amplification of various DNA probes. This review systematically summarizes the progress of fluorescence, PCR, and colorimetry-based BCA methods for the detection of various contaminants, including pathogenic bacteria, toxins, pesticides, antibiotics, and other chemical substances in food in over 120 research papers. Current challenges, including long experimental times and strict storage conditions, and the prospects for the application of BCA in biomedicine and environmental analyses, have also been discussed herein. [Display omitted] • Bio-barcode assay (BCA) is a novel rapid detection technology. • BCA has several advantages over conventional methods. • We summarize the concept and detection principles of BCA. • BCA has extensive applications in food testing. [ABSTRACT FROM AUTHOR]

Abstract New D-π-A type quinoline derivatives (CbzVQ and TPAVQ) were synthesized via Knoevenagel condensation reactions. They exhibited reversible high-contrast mechanofluorochromic (MFC) behavior under grinding/fuming treatment. Taking CbzVQ as an example, its fluorescence could be switched from blue to greyish green by grinding the as-synthesized sample into ground powders, and the fluorescence emission was red-shifted from 449 nm (with shoulders at 475 nm and 520 nm) to 578 nm (with shoulders at ca. 450 nm and 500 nm). Such large shift of the maximal emission peak during MFC processes was rare reported. In addition, the casting films of CbzVQ and TPAVQ emitted blue and green light, respectively, which was turned to red rapidly induced by TFA (trifluoroacetic acid) vapor. Moreover, the emission could be recovered stimulated by TEA (triethylamine) vapor, so the quinoline derivatives exhibited reversible fluorescent sensory properties. TPAVQ showed better performance in the detection of TFA vapor than CbzVQ due to the strong electron-donating ability of triphenylamine compared with carbazole. The detection limit and the decay time of TPAVQ towards TFA vapor were 163 ppb and 0.22 s, respectively. Apparently, the D-π-A type quinoline derivatives are candidates as multi-stimuli responsive fluorescent materials. Graphical abstract Image 1 Highlights • New D-π-A type quinoline derivatives bearing carbazole and triphenylamine are synthesized. • Quinoline derivatives show reversible high-contrast mechanofluorochromism. • The shift of the maximal emission for CbzVQ reaches 129 nm during mechanofluorochromic processes. • The emitting color of quinoline derivatives is turn to red from blue or green rapidly stimulated by TFA vapor. [ABSTRACT FROM AUTHOR]

Neural circuits can be reconstructed from brain images acquired by serial section electron microscopy. Image analysis has been performed by manual labor for half a century, and efforts at automation date back almost as far. Convolutional nets were first applied to neuronal boundary detection a dozen years ago, and have now achieved impressive accuracy on clean images. Robust handling of image defects is a major outstanding challenge. Convolutional nets are also being employed for other tasks in neural circuit reconstruction: finding synapses and identifying synaptic partners, extending or pruning neuronal reconstructions, and aligning serial section images to create a 3D image stack. Computational systems are being engineered to handle petavoxel images of cubic millimeter brain volumes. [ABSTRACT FROM AUTHOR]

Abstract New carbazole-modified pyrazole derivatives were synthesized. It was found that tert -butylcarbazole derivatives of TCPDP , TCPHP , TCPPM and TCPPF exhibited reversible mechanofluorochromic (MFC) behavior under the treatment of grinding/fuming with CH 2 Cl 2. Particularly, the emission of the as-synthesized crystals of TCPDP was weak and emerged in the ultraviolet region, while the grinding led to significant red-shift of the emission to the visible-light region, accompanied with the significant fluorescence enhancement on account of the formation of J -aggregates. Thus, TCPDP showed intriguing fluorescence switching in visible-light region during MFC processes, which could be easily observed visually. Additionally, TCPDP , TCPHP , TCPPM and TCPPF could form stable organogels in some organic solvents. Notably, the solutions of TCPPM and TCPPF were almost non-emissive, but gelation-induced blue emission was achieved. Thus, the fluorescence could be also turned on due to the AIE (aggregation-induced emission) during the gel formation. Graphical abstract Image 1 Highlights • New carbazole-modified pyrazole derivatives were synthesized. • Tert -butylcarbazole derivatives showed reversible mechanofluorochromism and good gelation abilities. • High-contrast mechanofluorochromism of TCPDP was achieved via fluorescence switching in visible-light region. • Gelation-induced emission of TCPPM and TCPPF was detected. [ABSTRACT FROM AUTHOR]

Abstract New tert -butylcarbazole modified β-diketone difluoroboron complexes CVB , PCVB , MPCVB and BPCVB have been synthesized. It was found that BPCVB without any traditional gelation group formed organogel in toluene, xylene, 1,3,5-triethylbenzene and 1,4-dioxane. The gained organogel and xerogel based on BPCVB gave a strong red fluorescence. The emission for the xerogel-based film was quenched by aniline vapor selectively, and the detection limit was as low as 2.0 ppb. It is interesting that the solid emission of the synthesized complexes was in the range of 600–850 nm, and the highest solid fluorescent quantum yield reached 0.37. These NIR dyes showed MFC behavior. For example, the as-synthesized sample of PCVB gave an emission band at 647 nm, and emitted red light under UV irradiation. The grinding of the as-synthesized sample resulted in the emitting color to turn to dark purple, accompanied with the red-shift of the emission to ca. 700 nm. The emission could recover to initial states by fuming the ground powders with CH 2 Cl 2 vapor. Based on the UV–vis spectra and XRD patterns in different solid-state for PCVB suggested that π-aggregates were formed in the as-synthesized crystals, and the grinding could destroy the aggregates and yield amorphous state. The transformation between crystalline and amorphous states led to MFC behavior. Graphical abstract Image 1 Highlights • New β-diketone difluoroboron complexes with high solid fluorescence quantum yields were synthesized. • BPCVB without any traditional gelation group formed organogels. • The xerogel-based film of BPCVB with red emission could detect gaseous aniline selectively. • These NIR dyes showed MFC behavior. [ABSTRACT FROM AUTHOR]

New difluoroboron β-carbonyl cyclic ketonate complexes CnB (n = 2, 16), in which carbazole was linked to difluoroboron β-diketonate directly, and DCnB (n = 2, 16), where two terminal carbazole units were bridged by vinyl groups to link to difluoroboron β-diketonate core, were synthesized. They exhibited reversible mechanofluorochromic (MFC) behavior under grinding/fuming or heating treatment. Particularly, the emission of DC2B and DC16B emerged in the range of 650–850 nm in the solid-state. They gave red and rose-red luminescence in the as-synthesized crystals and in the ground powders, respectively, during MFC processes. Such MFC materials emitting NIR (near-infrared) light were seldom reported. In addition, compared with C2B , C16B showed high-contrast mechanofluorochromism because the long alkyl chain might decrease the strength of π-π interactions in the as-synthesized crystals, leading to the emission appeared at the high-energy region (483 nm). The disassembling of parts of π-aggregates and the improvement of the molecular planarity led to red-shift of the emission (509 nm) upon grinding. [ABSTRACT FROM AUTHOR]

Herein, three new fluorostyrylindazoles bearing one, three and five fluorine atoms (FPIZ , TFPIZ and PFPIZ) have been synthesized. Interestingly, the crystal of PFPIZ bent back away from the lighht source at the initial stage of 365 nm light irradiation, and then it showed phototropic bending when prolong the irradiation time without changing the irradiation direction. It was found that the photo-induced [2 + 2] cycloaddition could lead to the expansion and contraction of the unit cell in different directions, and in turn trigger the crystal to exhibit macroscopic mechanical moving. Meanwhile, the photochemical reaction was reasonable for the photochromism of the PFPIZ , which is helpful for the visual observation of the photomechanical effects. For instance, the fluorescence of the crystals of PFPIZ was changed from blue-purple to white under 365 nm irradiation. Besides, TFA (trifluoroacetic acid) could quench the emission of the synthesized fluorostyrylindazoles to different degree in solutions as well as in the films. The acidochromism of the styrylindazole derivatives was originated from the protonation of indazole by acid. The design of multi-stimuli response crystalline materials would be helpful for the fabrication of intelligent photoactuators and fluorescence sensors. [Display omitted] • The molecular crystals based on (E)-1-methyl-3-(2-(perfluorophenyl)vinyl)-1 H -indazole exhibited photomechanical effects. • Stereospecific photo-induced [2 + 2] cycloaddition underwent in the crystal of PFPIZ. • The fluorescence of the crystals of PFPIZ was changed from blue-purple to white on account of the photodimerization. • The films of fluorostyrylindazoles could probe gaseous trifluoroacetic acid rapidly and sensitively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Five strains of LAB were associated with improved flavor. • LAB fermentation was associated with increased organic acid and decreased sugars. • Important metabolic compounds of different LAB fermentation were identified. • Specific strains can improve enzyme inhibition and antioxidant activities. • Isoquercitrin and m -coumaric acid content reflected the strain/species specificity. Lactic acid bacteria (LAB) have exhibited strain/species specificity for different food matrices. We investigated the impact of LAB fermentation on the flavor, chemical profile, and bioactivity of goji juice. The colony counts of five selected strains reached above 8.5 log CFU/mL. The fermentation increased the organic acids, decreased the sugars, and improved the sensory quality of goji juice. The majority of the strains had increased acetic acid, heptanoic acid, ethyl phenylacetate, and linalool levels. Specific strains suppressed α-glucosidase and pancreatic lipase activities and increased the antioxidant activities of fermented goji juice. Based on non-targeted metabolomics and activities, 23 important differential metabolites were screened among 453 metabolites. The quantification results showed that isoquercitrin and m -coumaric content varied among strains, reflecting the strain specificity in flavone and flavonol biosynthesis and phenylalanine, tyrosine, and tryptophan biosynthesis. These findings will provide useful information for fermented goji juice biochemistry research. [ABSTRACT FROM AUTHOR]

Four fluorescent low molecular weight gelators based on benzoxazole or benzothiazole functionalized pyrimidine were designed and synthesized. The ability of the target was tested, and all compounds could form stable supramolecular gels in an alcohol/water mixture and its fluorescence increased during gel formation. Photophysical spectra during gel formation, SEM, XRD, FT-IR study suggested that the self-assembly was driven by hydrogen bonding, van der Waals forces and weak π-π interaction. Interestingly, the gel collapsed after being illuminated by 365 nm UV light and 1H NMR of the gel before and after illumination proved that the [2 + 2]-cycloaddition between the double bond of pyrimidine was responsible for the light response. Furthermore, the fluorescent of xerogel film could be quenched by volatile acids while the fluorescent of the solution was enhanced after acid was added. The different phenomena were discussed. The nano-fiber assembled via gel formation could be used as fluorescent imaging material of latent fingerprints. [Display omitted] • Design and synthesis of novel uracil derivatives containing benzoxazole and benzothiazole. • Benzoxazole-modified uracil derivatives exhibit good gelation abilities and driving force of gel formation was investigated. • The gel could respond to light and acid. The response mechanism was studied. • The nano-materials assembled via gel formation could be used as fluorescent imaging material of latent fingerprints. [ABSTRACT FROM AUTHOR]

Three push-pull chromophores comprising a triphenylamine (TPA) as electron-donating moiety and functionalized β-diketones as electron acceptor units are studied by various spectroscopic techniques. The time-correlated single-photon counting data shows that increasing the number of electron acceptor units accelerates photoluminescence relaxation rate of compounds. Transient spectra data shows that intramolecular charge transfer (ICT) takes place from TPA units to β-diketones units after photo-excitation. Increasing the number of electron acceptor units would prolong the generation process of ICT state, and accelerate the excited molecule reorganization process and the relaxation process of ICT state. [ABSTRACT FROM AUTHOR]

New D-π-A type aminostyrylquinoxaline derivatives ( QDMA1 , QDMA2 , QTPA1 and QTPA2 ) were synthesized via Knoevenagel condensation reactions. It was found that their ICT (intramolecular charge transfer) emission were red-shifted significantly with increasing the solvent polarities. Interestingly, compound QTPA2 bearing two terminal triphenylamine groups exhibited reversible mechanofluorochromism. The emission of the as-synthesized crystals of QTPA2 was located at 542 nm, and it was red-shifted to 592 nm upon grinding, so the emitting color was changed from yellow to carmine. Meanwhile, the emission could be recovered when the ground powders were fumed with DCM vapor. XRD patterns and DSC curves in different solid states demonstrated that the mechanofluorochromism was due to the transformation between the crystalline and amorphous states. In addition, the protonation of the synthesized aminostyrylquinoxalines by TFA could lead to the colors of the solutions to change into dark green from yellow, accompanied with the quenching of the emission. Furthermore, we also found that the emission of QTPA2 in the film could be quenched significantly and rapidly stimulated by TFA vapor, and the detection limit and the decay time were estimated to be 167 ppb and 0.47 s, respectively. Therefore, the aminostyrylquinoxaline derivatives could be used as sensory materials to detect acids in solutions and in the films by naked eyes. [ABSTRACT FROM AUTHOR]

Efficacious and convenient removal of organic dye contaminants from wastewater is a challenge for public health and ecosystem protection. Here we fabricate a novel type of Fe 3 O 4 @MOFs (Metal-organic frameworks) magnetic porous composite materials. ZIF-67 (Zeolitic imidazolate framework-67) nano-crystals as an attractive subfamily of MOF was selected to fabricate Fe 3 O 4 -PSS@ZIF-67 composites (defined as MZIF-67). MZIF-67 composites are core-shell structure, for which the aggregation core of Fe 3 O 4 nanoparticles is coated with petal-like ZIF-67 crystals, in which Co 2+ firstly combines with SO 3 2− provided by PSS (poly (styrenesulfonate, sodium salt)) to form nucleation. MZIF-67 composites perform well on methyl orange (MO) adsorption, which could be attributed to the highly porosity and the nature of Lewis base of coordinated Co 2+ centrals. The results show that the equilibrium adsorption capacity for MO is up to 738 mg·g −1 (when pH = 8.0, contact time is 7 h, adsorbent dose is 5 mg and initial MO concentration is 400 mg·L −1 ). In addition, MZIF-67 composites could selectively separate MO from the mixture solution of MO and MB (methylene blue). The removal rate of MO is up to 92%. The concentration ratio of MO/MB is 0.04. And the separation efficiency is up to 96%. The results suggest MZIF-67 composites could be a good candidate for treatment of dye-bearing wastewater. [ABSTRACT FROM AUTHOR]

New difluoroboron β-ketoiminate boron complexes bearing benzoxazole ( CBO ) and benzothiazole ( CBS ) have been synthesized. It was found that CBO was almost non-emissive in THF, and the emission could be intensified significantly when great amount of H 2 O was added, illustrating AIE (aggregation-induced emission) property. CBS could not show AIE property in THF/H 2 O system, but its emission in solid state was also strong. The single crystal structure of CBS suggested that π-π interactions and the hydrogen bonds of C(Ar)−F⋅⋅⋅H, C(Ar)−H⋅⋅⋅S and C(Ar)−H⋅⋅⋅Cl would suppress the rotation of single bonds, resulting into obvious emission enhancement. It is interesting that the as-synthesized crystals of CBO and CBS both emitted azure light, and the grinding made their emitting colors to change into cyan and green, which could be recovered under fuming with DCM or heating. The reversible mechanofluorochromism was due to the transformation between crystalline and amorphous states, which could be confirmed from the results of absorption spectra, XRD patterns and DSC curves in different solid states. Additionally, the high-contrast mechanofluorochromism of CBS compared with CBO might be originated from the loose packing in crystalline state and the better π-electron delocalization. [ABSTRACT FROM AUTHOR]

New β-diketone-boron difluoride complexes functionalized with tetraphenylethene ( TPEB , DTPEB and TTPEB ) which exhibit AIE (aggregation-induced emission) properties have been synthesized. It was found that only boomerang-shaped DTPEB without any traditional gelation groups could form organogel in specific organic solvents. It gave strong orange red fluorescence in organogel as well as in xerogel-based film although it was non-emissive in solution. It is interesting that the emission of DTPEB in xerogel-based film could be quenched significantly upon exposure to triethylamine (TEA) vapour, and the detection limit was as low as ca. 0.1 ppb. This work provides a strategy for the synthesis of a new rigid non-traditional π-gelator via the construction of a boomerang-shaped π-conjugated skeleton. In addition, the gelation of the π-gelators with AIE ability is a facile method for the fabrication of luminescent organic nanomaterials. [ABSTRACT FROM AUTHOR]

Two push-pull compounds, which are comprised of triphenylamine (TPA) (electron donor units) and functionalized β-diketones difluorboron complexes (electron acceptor units) are probed by many spectroscopies, which offers the relationship between electron acceptor and the intrinsic excited state properties of push–pull chromophores. We found that the photoluminescence (PL) intensity would enhance with the number of electron acceptor. Transient absorption (TA) data shows that intramolecular charge transfer (ICT) process really exists in the two molecules after photoexcitation and this process would be prolonged through increasing the electron-acceptor, which would be responsible for the improvement of PL property. [ABSTRACT FROM AUTHOR]

• RAN promoted the polarization of macrophages towards M1 by activating the PI3K/Akt2/NF-κB signaling pathway. • p-Akt2 can enhance the endocytosis of macrophages by regulating GSK3β/Dynamin1 pathway. • RAN as adjuvant could effectively increase the differentiation of Th1 cells after M1 polarization. • RAN could enhance the killing function of CTL to inhibit tumor growth and improve survival rate as adjuvant tumor vaccine. Adjuvants are an indispensable component of vaccines, but there are few adjuvants for human vaccines. H2 receptor blockers, inhibiting gastric acid secretion, have immune enhancement effects. Ranitidine (RAN) is a water-soluble H2 receptor blocker, and whether it has an immune-enhancing effect is still unknown. In this study, flow cytometry, western blotting, and immunofluorescence methods were used to analyze whether RAN could activate macrophage polarization to the M1 phenotype in vivo and in vitro. Here, we found that the M1 inflammatory cytokine levels and surface markers in RAW264.7 cells were upregulated by NF-κB activation, possibly through the PI3K-Akt2 signaling pathway, after RAN treatment. Endocytic function was also enhanced by feedback regulation of Akt2/GSK3β/Dynmin1 signaling. Furthermore, to evaluate the adjuvant function of RAN, we used OVA plus RAN as a vaccine to inhibit the growth of B16-OVA tumors in mice. We also found that in the RAN adjuvant group, macrophage polarization to M1, Th1 cell differentiation, and cytotoxic T lymphocyte (CTL) activation were significantly upregulated. The tumor growth of mice was inhibited, and the survival rate of mice was significantly improved. This study provides new evidence for the mechanism by which RAN activates the immune response and is expected to provide a new strategy for the research and development of tumor vaccine adjuvants. [ABSTRACT FROM AUTHOR]

[Display omitted] • An all-in-one MoS 2 -based electrocatalyst for hydrogen evolution is constructed by inkjet printing. • Inkjet-printed 3D architecture contributes to the exposure of active catalytic sites. • 1T-MoS 2 surrounded by graphene reduces the charge-transfer impendence. • Cu contact supports the efficient electron injection from the electrode to catalytic materials. • The facile and scalable avenue allows the fabrication of electrocatalysts with high throughput. 2D transition metal dichalcogenides (TMDs) are emerging as promising alternative electrocatalysts for hydrogen evolution reaction (HER). However, key challenges are the limited density of available activity sites and poor electron accessibility. Herein, Cu film supported MoS 2 -based electrocatalyst with partial 1T phase and 3D architecture is constructed by inkjet printing. We aim to investigate if this configuration could provide largely exposed edge sites and enhance electron transfer for ultra-efficient hydrogen production. Towards this end, an ink containing few-layer MoS 2 nanosheets and reduced graphene oxide (RGO) is firstly prepared by liquid-phase exfoliation, in which semiconducting 2H-MoS 2 is partially transformed to metallic 1 T-MoS 2. We demonstrate that 1) nanosized few-layer MoS 2 spatially patterned by inkjet-printing provides sufficient active site exposure, 2) the 1T-MoS 2 and RGO conductive network reduce the charge-transfer impedance, and 3) the Cu support enhances the catalyst-electrode charge injection. Our all-in-one structure exhibits outstanding HER activities with low overpotential (51 mV at 10 mA cm−2 and 126 mV at 100 mA cm−2) and very low Tafel slope (32 mV dec-1). Also, the as-engineered electrode demonstrates ultrahigh cathodic current density. This work provides a facile, inexpensive, and scalable way for designing and fabricating TMDs-based electrocatalysts with excellent HER activity. [ABSTRACT FROM AUTHOR]

New tert -butylcarbazole-based Schiff bases TPMP and TPMA , as well as the difluoroboron complex of salicylaldimine TPOB were synthesized. It was found that TPMP and TPMA without any traditional gelation group could form organogels in toluene and o -dichlorobenzene, etc., stimulated by ultrasound. It was suggested that the planar π-skeletons and the large steric effect of tert -butyl groups would lead to appropriate π-π interaction to induce the gel formation. Interestingly, the nanofibers formed from salicylaldimine derivative TPMP could emit strong yellowish green light under UV irradiation. It should be noted that the difluoroboron complex of TPOB with non-planar aromatic unit could not gelate the selected solvents on account of the weak π-π interaction. However, it showed reversible piezofluorochromism. The as-prepared crystal of TPOB emitted strong yellow light and could be transformed into the powders emitting orange red light after grinding, and the fluorescence could recover when the ground powders were heated. Such reversible changes of the emitting colors for TPOB by the treatment of grinding and heating was resulted from the transformation between crystalline and amorphous states. Herein, we provided the strategy for fabricating new nontraditional π-gels directed by appropriate π-π interaction and new piezofluorochromic dyes via the introduction of non-planar π-skeletons. [ABSTRACT FROM AUTHOR]

• BAI treatment delayed the onset of EAE, alleviate clinical symptoms, demyelination and inflammatory cell infiltration. • BAI inhibited the overactivation of M1 microglia/macrophages in vivo and in vitro, significantly decreased the expression of proinflammatory cytokines in M1 microglia/macrophages. • BAI has the binding ability to the SH2 domain of STAT1, and leaved P-STAT1 in the cytoplasm rather than transferred to the nucleus during inflammatory stimulation. Microglia/macrophage polarization modulation plays a key role in the pathogenesis of multiple sclerosis (MS)/experimental autoimmune encephalomyelitis (EAE). M1 microglia/macrophages secrete a variety of cytokines that cause inflammation and facilitate demyelination in the central nervous system (CNS). Baicalein (5,6,7-trihydroxyflavone, C 15 H 10 O 5 , BAI), a natural flavonoid isolated from the roots of the traditional Chinese medicine Scutellaria baicalensis Georgi, has been suggested to have a wide range of biological effects, including antioxidant, anti-inflammatory, and neuroprotective properties. In this study, flow cytometry, Western blotting, immunofluorescence and other methods were used to investigate whether BAI could reduce the demyelination and inflammatory response of the spinal cord in EAE mice induced by MOG 35-55 and affect the polarization of spinal microglia/macrophages. Our results showed that BAI treatment delayed the onset of EAE and alleviated clinical symptoms, demyelination and inflammatory cell infiltration. Meanwhile, BAI inhibited the overactivation of M1 microglia/macrophages in vivo and in vitro, significantly decreased the expression of proinflammatory cytokines in M1 microglia/macrophages, and inhibited the activation of STAT1. Subsequently, molecular docking, pull-down and immunofluorescence experiments confirmed that BAI has the ability to bind to the SH2 domain of STAT1 and that BAI colocalizes with p-STAT1 in the cytoplasm rather than being transferred to the nucleus during inflammatory stimulation. This study showed that BAI might inhibit the polarization of microglia/macrophages to the M1 phenotype in EAE mice by targeting STAT1. This new discovery lays a theoretical and experimental foundation for the clinical application of BAI in the treatment of MS. [ABSTRACT FROM AUTHOR]

Axially wrinkled SnO 2 /TiO 2 heteronanotubes have been successfully prepared by sacrificial template method combined with hydrothermal synthesis. The special folded morphology of SnO 2 /TiO 2 nanostructures may provide more active sites, and the S-scheme heterojunction between SnO 2 and TiO 2 enhances the separation of photogenerated electron-hole pairs, which are conducive to the improvement of photocatalytic degradation for organic pollutants. Using SnO 2 /TiO 2 nanotubes as catalyst, the removal rate of Rhodamine B (RhB), methyl orange (MO) and tetracycline hydrochloride (TCH) under the irradiation of a xenon lamp is 93%, 91% and 85%, respectively. After five cycles, the removal efficiency of organic pollutants maintains almost unchanged, indicating that the synthesized SnO 2 /TiO 2 nanotubes has good stability and reusability. In addition, trapping experiments have been carried out to investigate the major reactive oxidative species for organic pollutants photodegradation. This study provides a facile avenue to design nanotublar photocatalysts with enhanced degradation performance for organic pollutants. [ABSTRACT FROM AUTHOR]

New difluoroboron β-diketonate complexes functionalized with tert -butyl carbazole and carbazole ( TCBM and CBM ) have been synthesized, and they give strong emission in solid states with the fluorescence quantum yields of 0.63 and 0.99, respectively. Reversible mechanofluorochromic behaviors of TCBM and CBM are realized upon the treatment of grinding/fuming with CH 2 Cl 2 . Interestingly, the emitting colors of the annealed samples gained from the ground powders of TCBM depend on the heating temperature, and change from orange to yellow, yellowish green, and green with increasing temperature. The X-ray diffraction patterns illustrate that the transformation processes from crystalline structure to partial destroyed crystalline structure, till to amorphous state lead to the multi-color solid-state luminescence during thermofluorochromism. We deduced that tert -butyl can lead to the incompact packing of luminophores, which is more sensitive to external stimuli, so that multi-color solid-state luminescence can be afforded during mechanofluorochromic and thermofluorochromic processes. [ABSTRACT FROM AUTHOR]

New indolocarbazole derivatives have been synthesized via Cadogan reaction. It has been found that the reductive cyclization of 3-(2-nitrophenyl)carbazoles prefers to take place on 4-position instead of 2-position in carbazole rings. Because electrophilic substitution was one of the main steps in Cadogan reaction and the Fukui function analysis for 9-methyl-3-(2-nitrophenyl)-9 H -carbazole revealed that more positive part of f − ( r ) function was localized at 4-position than at 2-position in carbazole, the 4-position was the favorite reactive site for the reductive cyclization. Such regioselective Cadogan reaction would be useful for the synthesis of π-extended N -fused heteroacenes with desired functionalities. [ABSTRACT FROM AUTHOR]

To prepare colorless polyimides (CPIs), two novel diamines, namely 6-amino-2-(2′-methyl-4′-aminobenzene)-N-phenylbenzimidazol (5a) and 6-amino-2-(2′-trifluoromethyl-4′-aminobenzene)-N-phenylbenzimidazol (5b) were synthesized, and two series of polyimides derived from them were developed. Except for the inherent asymmetric structures, the twisted moieties had been successfully incorporated in the benzimidazole dianmines through 2′- and N-substituents. The loose chain packing and hindered charge transfer (CT) interaction caused by the askew and distorted segments provided the polyimides with excellent optical transparency (80% transmittance at 400 nm, semi-alicyclic series), while the resulting films inherited the unique superheat-resistance of poly(benzimidazole imide)s (PBIIs), e.g., high glass-transition temperatures (up to 402 °C). Such outstanding optical and thermal properties expanded their application as heat-resistant colorless materials. Furthermore, the correlation between various 2′-substituents and characters of these PBII films was systematically analyzed. These data indicated that these colorless polyimides had potential application as optical and optoelectronic materials. [Display omitted] • Two novel benzimidazole dianmines containing 2′- and N-substituents (5a and 5b) were successfully synthesized. • Polyimide films with asymmetric and twisted structures were successfully synthesized. • The semi-aromatic poly(benzimidazole imide) films achieved colorlessness (T 400 = 80–81% and T g = 394–402 °C). • The effect of various 2′-substitutions on the properties of these N-phenyl-poly(benzimidazole imide)s was investigated. [ABSTRACT FROM AUTHOR]

New triphenylvinyl substituted carbazole derivatives TPEICE , TPEC and TPECBr have been synthesized. They could self-assemble into nanofibers via organogelation processes in some organic solvents. Notably, the obtained xerogel-based films could emit strong fluorescence although the three compounds were non-emissive in solutions, indicating AIE in gel phases. The emission of TPEICE and TPEC in xerogel-based films could be quenched significantly upon exposed to gaseous DNT and TNT, while TPECBr could not sense nitro compounds on account of its poor electron donating ability. We also found that reversibility of the fluorescence response of TPEC was better than TPEICE because the photo-induced electron transfer would happen during the recognition of nitroaromatics for TPEICE and TPEC , except for the formation of charge–transfer complex between TPEICE and nitro compounds. Therefore, the different fluorescence response behaviors of TPEICE , TPEC and TPECBr towards nitroaromatics were resulted from their different electron donating abilities. [ABSTRACT FROM AUTHOR]

New branched benzothiadiazole-cored conjugated oligomers with terminal carbazoles 1 and 2 have been synthesized. It was found that no obvious shifts of the maximal absorption bands for 1 and 2 were detected in the films compared with those in solutions, indicating weak π-π stacking occurred in the solid states on account of site isolation effect of the branched architectures. Hence, the synthesized oligomers could emit strong red light in the films. Notably, the emission of the films based on 1 and 2 could be quenched obviously upon exposed to gaseous TNT and DNT. The fluorescence quenching efficiency of the oligomer 2 -based film reached 91% when exposed to the saturated vapor of DNT for 3 min at 55 °C. The linear Stern–Volmer plot and the decrease of the fluorescence lifetime of 2 induced by DNT suggested the fluorescence sensing mechanism was due to the photo-induced electron transfer. [ABSTRACT FROM AUTHOR]

The promoting effect of secondary phase particles on the refinement of matrix grains in a series of Mg–Y1.5–Nd0.6-Zn. x ( x =0, 0.2, 0.4, 0.8, 1.3) alloys deformed by friction stir processing (FSP) was investigated in this study. The volume fraction of secondary phase in the alloys increased with increment of Zn, and most of the secondary phases were broken into nano-sized particles and dispersed in the matrix during thermal mechanical processing. The resulting fine particles had a remarkable promoting effect on the grain refinement of the Mg matrix during mechanical processing, thermal deformation, and cooling with increasing volume fraction of the secondary phase. For example, the grains of Mg–Y1.5–Nd0.6–Zn1.3 alloy were refined to an average size of 28 nm, compared with the more than 100 nm grain size of the Mg–Y1.5–Nd0.6 alloy. [ABSTRACT FROM AUTHOR]

A benzoxazole derivative called BVDA was synthesized. BVDA exhibited an AIE effect although there was H-aggregated dimer in the crystal. According to the spectral results and crystal structure, the presence of excimer and the restriction of intramolecular rotation are responsible for the AIE phenomenon. Moreover, BVDA could respond to proton in solution and to volatile acid vapours in film. BVDA exhibited three colours because its binding sites to proton have different basicities. These binding sites can then be protonated in turn. These results indicate that AIE fluorophores with H-aggregated dimer is possible. Furthermore, these fluorophores can exhibit stimuli-responsive characteristics through the introduction of functional moieties. [ABSTRACT FROM AUTHOR]

Zebrafish Fish-egg lectin (zFEL) has been identified and proved to be a maternal factor with antibacterial and opsonic ability in fishes. In this study, we found that zFEL was capable of enhancing the phagocytosis of the bacteria by macrophages of mouse (RAW264.7 and mouse peritoneal macrophages), suggesting a cross-species function of zFEL in higher animals. Further studies showed that zFEL can active the antigen presentation ability by up-regulating the expression of CD80, CD86 and MHC II. Meanwhile, zFEL also promoted the polarization of macrophages to M1-type, which was confirmed by the increase of cytokines TNF-α and IL-6. The expression of p38 gene was up-regulated in macrophages preincubated with zFEL. Taken together, zFEL appears opsonic function in mammal macrophages and has potential application in immunomodulation. • Cross-species opsonic activity is found by zebrafish fish-egg lectin (zFEL) on mouse macrophages. • zFEL can up-regulate the expression of CD80, CD86 and MHC II on macrophages. • zFEL promotes the polarization of macrophages to M1-type. [ABSTRACT FROM AUTHOR]