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As the most classic photoisomerization system, azobenzene has been widely utilized as a building unit in various photoswitching applications. However, attempts to build azobenzene-based single-molecule photoswitches have met with limited success, giving low on/off ratios. Herein, we demonstrate two designs of azobenzene-based photoresponsive single-molecule junctions, based on mechanically interlocked diazocine and azobenzene-based dynamic anchors, respectively. Molecular conductance measurements using the scanning tunneling microscope breaking junction (STMBJ) technique revealed dramatic conductance changes upon photoillumination, achieving a high on/off ratio of ∼3.7. Using density functional theory (DFT), we revealed peculiar quantum interference (QI) effects in the diazocine molecular switch, indicating that diazocine is an excellent candidate for molecular photoswitches. The asymmetric azobenzene devices with a dynamic anchor exhibit switching behavior between a fully off state and a highly conductive state associated with the trans / cis conformation transition. The findings of this work not only present the design and development of functional molecular devices based on azobenzene units but also provide insight into the fundamental properties of light-induced quantum interference in azobenzene-based molecular devices.

Given the rapid developments in modern devices, there is an urgent need for shape-memory polymer composites (SMPCs) in soft robots and other fields. However, it remains a challenge to endow SMPCs with both a reconfigurable permanent shape and a locally reversible shape transformation. Herein, a dynamic cross-linked network was facilely constructed in carbon nanotube/ethylene vinyl acetate copolymer (CNT/EVA) composites by designing the molecular structure of EVA. The CNT/EVA composite with 0.05 wt % CNT realized a steady-state temperature of ∼75 °C under 0.11 W/cm 2 light intensity, which gave rise to remote actuation behavior. The dynamic cross-linked network along with a wide melting temperature offered opportunities for chemical and physical programming, thus realizing the achievement of the programmable three-dimensional (3D) structure and locally reversible actuation. Specifically, the CNT/EVA composite exhibited a superior permanent shape reconfiguration by activating the dynamic cross-linked network at 140 °C. The composite also showed a high reversible deformation rate of 11.1%. These features endowed the composites with the capability of transformation to 3D structure as well as locally reversible actuation performance. This work provides an attractive guideline for the future design of SMPCs with sophisticated structures and actuation capability.

β-1,3-Glucan synthases play key roles in glucan synthesis, cell wall assembly, and growth of fungi. However, their multi-transmembrane domains (over 14 TMHs) and large molecular masses (over 100 kDa) significantly hamper understanding of their catalytic characteristics and mechanisms. In the present study, the 5841-bp gene CMGLS encoding the 221.7 kDa membrane-bound β-1,3-glucan synthase CMGLS in Cordyceps militaris was cloned, identified, and structurally analyzed. CMGLS was partially purified with a specific activity of 87.72 pmol/min/μg, a purification fold of 121, and a yield of 10.16% using a product-entrapment purification method. CMGLS showed a strict specificity to UDP-glucose with a K m value of 84.28 μM at pH 7.0 and synthesized β-1,3-glucan with a maximum degree of polymerization (DP) of 70. With the assistance of AlphaFold and molecular docking, the 3D structure of CMGLS and its binding features with substrate UDP-glucose were proposed for the first time to our knowledge. UDP-glucose potentially bound to at least 11 residues via hydrogen bonds, π-stacking ,and salt bridges, and Arg 1436 was predicted as a key residue directly interacting with the moieties of glucose, phosphate, and the ribose ring on UDP-glucose. These findings would open an avenue to recognize and understand the glucan synthesis process and catalytic mechanism of β-1,3-glucan synthases in mushrooms.

Composites based on a shape-memory polymer doped with conductive particles are considered as soft actuators for artificial muscles and robots. Low-voltage actuating is expected to reduce equipment requirement and safety hazards, which requires a highly conductive particle content but weakens the reversible deformation. The spatial distribution of the conductive particle is key to decreasing the actuating voltage and maintaining the reversible deformation. Herein, an approach of fabricating a low-voltage actuator that can perform various biomimetic locomotions by spraying and hot pressing is reported. Carbon nanotubes (CNTs) are enriched inside the surface layer of poly(ethylene- co -vinyl acetate) (EVA) to form a high-density conductive network without degradation of the reversible deformation. The bilayer CNT/EVA actuator exhibits a reversible transformation of more than 10% even with 100 cycles, which requires an applied voltage of just 15 V. Taking advantage of the reprogrammability of the CNT/EVA actuator and reversible shift between the different shapes, different biomimetic locomotions (sample actuator, gripper, and walking robot) are demonstrated without any additional mechanical components. A scheme combining the electrical properties and the shape-memory effect provides a versatile strategy to fabricate low-voltage-actuated polymeric actuators, providing inspiration in the development of electrical soft actuators and biomimetic devices.

Conductive textiles (CTs) are promising electromagnetic interference (EMI) shielding materials. Nevertheless, limited stretchability and poor reliability restrict their potential applications in stretchable electronic devices because of the rigid conductive networks. Herein, a highly stretchable and reliable CT is developed for effective EMI shielding by designing a deformable liquid-metal (LM) coating and polydimethylsiloxane (PDMS) protective layer. The resultant PDMS-LM/Textile exhibits an outstanding EMI shielding efficiency (EMI SE) of 72.6 dB at a thickness of only 0.35 mm while maintaining EMI SEs of 66.0 and 52.4 dB under strains of 30 and 50%, respectively. The corresponding EMI SEs hold 91.7 and 80.3% retention after 5000 stretching-releasing cycles, respectively. The superior and durable EMI SE should be ascribed to the perfect connectivity and good deformability of conductive LM networks. Moreover, the LM coating has a robust fastness to the textile substrate, without any obvious decrease in EMI SE after 10 min of ultrasonic treatment and 100 peeling cycles because of the protective effect of the PDMS layer. This work provides a novel route to developing highly stretchable CTs for advanced EMI shielding applications, especially in the field of highly stretchable electronic devices.

Clerodendranthus spicatus , popularly known as "kidney tea" in China, is consumed traditionally as a functional food for treatment of renal inflammation, dysuria, and gout. We evaluated the effects of C. spicatus on gout by assessing activities of antihyperuricemia, anti-gouty arthritis, and analgesia in vivo , and the results indicated that the ethyl acetate fraction shows potential activities. Subsequent phytochemical investigation of this fraction led to the isolation of 32 compounds, consisting of 20 diterpenoids (including the new orthosiphonones E and F), 2 triterpenoids, 6 flavonoids, 2 lignanoids, and 2 phenolic acid derivatives. Pharmacological investigation of the pure compounds in the cellular model of hyperuricemia indicated that 12 compounds could promote the excretion of uric acid at 10 μg/mL, and compounds 3 , 4 , 5 , and 21 had better effects than that of benzbromarone, a famous uricosuric drug. Furthermore, compounds 4 , 6 , 7 , 9 , 14 , 15 , 23 , 26 , and 31 showed significant anti-gouty arthritis activity in monosodium urate (MSU)-induced joint swelling at the dose of 50 mg/kg, while compounds 4 , 5 , 7 , 9 , and 26 exhibited significant inhibition of pain induced by acetic acid. Our findings provided scientific justification to support the traditional application of "kidney tea" for treating gout and suggested its good application prospects in the future.

MXenes are a new type of two-dimensional material, and they have attracted extensive attention because of their outstanding conductivity and rich surface functional groups that make surface engineering easy and possible for adapting to diverse applications. However, there are scarce studies on surface engineering of MXene. Herein, we demonstrate for the first time that octylphosphonic acid-modified Ti 3 C 2 T x MXene can be used as an active layer for memory devices and exhibits stable ternary memory behavior. Low threshold voltage, steady retention time, clearly distinguishable resistance states, high ON/OFF rate, OFF/ON1/ON2 = 1:10 2.7 :10 4.1 , and considerable ternary yield (58%) were obtained. In the proof of the mechanism, in situ conductive atomic force microscopy was conducted and the electrode-area relationship was analyzed to demonstrate that charge trapping and filament conduction are more suitable in the nonvolatile information memory of Ti 3 C 2 T x -OP MXene devices. In addition, a polyethylene-terephthalate-based flexible Ti 3 C 2 T x -OP memory device can maintain its stable ternary memory performance after being bent 5000 times. This work provides an easy method for surface modification of MXene and broadens the field of MXene.

Excellent electromagnetic interference (EMI) shielding ability, light weight, and good heat resistance are highly required for practical applications of EMI shielding materials, such as in areas of aerospace, aircraft, and automobiles. Herein, a lightweight and robust carbon nanotube (CNT)/polyimide (PI) foam was developed for efficient and heat-resistant EMI shielding. Thanks to poly(vinyl pyrrolidone) (PVP) as a surfactant that not only promotes the uniform dispersion of CNTs to form perfect CNT conductive networks but also can be removed in situ during the polymerization process, the density of resultant CNT/PI foam is only 32.1 mg·cm -3 , and the EMI shielding effectiveness (EMI SE) is up to 41.1 dB, which represents one of the highest EMI SE values compared to previously reported polymer-based foams. The CNT/PI foam also achieves the absorption coefficient ( A ) of up to 82.3%, which is very impressive in CNT/polymer foams at comparable EMI SE levels. The PI matrix endows the foam with excellent heat resistance. The as-prepared CNT/PI foam presents a higher EMI SE than 35 dB even after being subjected to the flame of an alcohol burner. Moreover, the compressive strength and compressive modulus are up to 240.9 and 323.9 kPa. These results indicate its certain application potential in the harsh requirement of aeronautics and aerospace industries as a highly efficient and lightweight EMI shielding material.

Sensitive fluorescence turn-on response to specific substances is highly desired for development of chemical sensors and switches. Here we utilized a "two-in-one" strategy to prepare ionic metal-organic frameworks (MOFs) functionalized with the cationic bipyridinium receptors at the frameworks and anionic fluorescent indicators in the pores. The MOFs are rendered a fluorescence-resting state because the indicator's fluorescence is efficiently quenched by the ground-state charge-transfer (CT) complexation between the indicator and receptor. Addition of an alkylamine efficiently turns on the fluorescence because the indicator is displaced by the CT complexation between alkylamine with receptor. The turn-on response is highly specific to alkylamines. The MOFs can be used as recyclable sensors for selective and sensitive detection of alkylamines, with ultralow detection limits (0.5 nM). The fluorescence in solid state can be reversibly switched on and off with high contrast. The sensitive and high-contrast response can be attributed to the space confinement effects of the porous frameworks. The confined space can significantly enhance indicator-receptor and analyte-receptor interactions, and thereby both the quenching efficiency in the off state and the displacement efficiency in the on state are amplified.

Flexible strain sensors based on elastomeric conductive polymer composites (ECPCs) play an important role in wearable sensing electronics. However, the achievement of good conjunction between broad detection range and high sensitivity is still challenging. Herein, a highly stretchable and sensitive strain sensor was developed with the formation of porous segregated conductive network in the carbon nanotube/thermoplastic polyurethane composite via a facile and nontoxic compression-molding plus salt-leaching method. The strain sensor with porous segregated conductive network exhibited perfect combination of ultrawide sensing range (800% strain), large sensitivity (gauge factor of 356.4), short response time (180 ms) and recovery time (180 ms), as well as superior stability and durability. The integrated porous structure intensifies the deformation of segregated conductive network when tension strain is applied, which benefits enhancement of the sensitivity. Our sensor could monitor not only subtle oscillation and physiological signals but also energetic human motions efficiently, revealing promising potential applications in wearable motion monitoring systems. This work provides a unique and effective strategy for realizing ECPCs based strain sensors with excellent comprehensive sensing performances.

Glucan synthase (GLS) gene is known to be involved in the fungal biosynthesis of cell wall, differentiation, and growth. In the present study, a glucan synthase gene ( GFGLS ) in the edible mushroom Grifola frondosa with a full sequence of 5927 bp encoding a total of 1781 amino acids was cloned and characterized for the first time. GFGLSp is a membrane protein containing two large transmembrane domains connected with a hydrophilic cytoplasmic domain. With a constructed dual promoter RNA silencing vector pAN7-gfgls-dual , a GFGLS- silencing transformant iGFGLS-3 had the lowest GFGLS transcriptional expression level (26.1%) with a shorter length and thinner appearance of the mycelia, as well as decreased mycelial biomass and exo -polysaccharide production of 5.02 and 0.38 g/L, respectively. Further analysis indicated that GFGLS silence influenced slightly the monosaccharide compositions and ratios of mycelial and exo -polysaccharide. These findings suggest that GFGLS could affect mycelial growth and polysaccharide production by downregulating the glucan synthesis.

Superhydrophobic electromagnetic interference (EMI) shielding textile (EMIST) is of great significance to the safety and long-term service of all-weather outdoor equipment. However, it is still challenging to achieve long-term durability and stability under external mechanical deformations or other harsh service conditions. Herein, by designing and implementing silver nanowire (AgNW) networks and a superhydrophobic coating onto a commercial textile, we demonstrate a highly robust superhydrophobic EMIST. The resultant EMIST shows a synergy of high water contact angle (160.8°), low sliding angle (2.9°), and superior EMI shielding effectiveness (51.5 dB). Remarkably, the EMIST still maintains its superhydrophobic feature and high EMI shielding level (42.6 dB) even after 5000 stretching-releasing cycles. Moreover, the EMIST exhibits strong resistance to ultrasonic treatment up to 60 min, peeling test up to 100 cycles, strong acidic/alkaline solutions, and different organic solvents, indicating its outstanding mechanical robustness and chemical durability. These attractive features of the EMIST are mainly a result of the joint action of AgNWs, carbon nanotubes, polytetrafluoroethylene nanoparticles, and fluoroacrylic polymer. This work offers a promising approach for the design of future durable, superhydrophobic EMISTs, which are capable of remaining fully functional against long-time exposure to extreme conditions, for example, wet and corrosive environments.

Eugenol, a plant-derived small compound, shows great medicinal potential. However, whether and how eugenol regulates crop physiology remains elusive. Here we reported that eugenol induced Cd (cadmium) tolerance in the root of Brassica rapa. Roots were treated with eugenol and CdCl 2 simultaneously (eugenol + Cd) or pretreated with eugenol followed by CdCl 2 treatment (eugenol → Cd). Eugenol significantly attenuated Cd-induced growth inhibition, ROS accumulation, oxidative injury, and cell death, which were confirmed by in vivo histochemical analysis. Eugenol remarkably decreased free Cd 2+ accumulation in root. Eugenol intensified GSH (glutathione) accumulation in roots upon CdCl 2 exposure, which explained the decrease in free Cd 2+ and attenuation of oxidative injury. Eugenol stimulated endogenous H 2 S (hydrogen sulfide) generation by upregulating the expression of BrLCD ( l-cysteine desulfhydrase) and BrDCD ( d-cysteine desulfhydrase) as well as their enzymatic activities in CdCl 2 -treated root. Application of H 2 S biosynthesis inhibitor or H 2 S scavenger led to the decrease in endogenous H 2 S level in Cd-treated root, which further compromised all the above effects of eugenol. These findings suggested that eugenol triggered H 2 S → GSH signaling cassette in plants to combat Cd stress, which shed new light on eugenol-modulated plant physiology and the interaction between eugenol and H 2 S.

Modification of the sterol catabolism pathway in mycobacteria may result in the accumulation of some valuable steroid pharmaceutical intermediates, such as 9α-hydroxy-4-androstene-3,17-dione (9-OHAD). In previous work, sigma factor D (SigD) was identified as a negative factor of the 9-OHAD production in Mycobacterium neoaurum. Here, the deficiency of rip1 putatively coding for a regulated intramembrane proteolysis metalloprotease (Rip1), which could cleave the negative regulator of SigD (anti-SigD), enhanced the transcription of some key genes (choM1, kshA, and hsd4A) in the sterol catabolic pathway. Furthermore, the deletion of rip1 increased the consumption of phytosterols by 37.8% after 96 h of growth in M. neoaurum. The production of 9-OHAD in the engineered M. neoaurumΔkstD1ΔkstD2ΔkstD3Δrip1 (MnΔk123Δrip1) strain was ultimately increased by 27.3% compared to that in its parental strain M. neoaurumΔkstD1ΔkstD2ΔkstD3 (MnΔk123). This study further confirms the important role of SigD-related factors in the catabolism of sterols.

This study aimed to construct objective and accurate analytical models of tea categories based on their polyphenols and caffeine. A total of 522 tea samples of 4 commonly consumed teas with different fermentation degrees (green tea, white tea, oolong tea, and black tea) were analyzed by high-performance liquid chromatography (HPLC) coupled with spectrophotometry, utilizing ISO 14502, as analytical tools. The content of polyphenols and caffeine varied significantly according to differently fermented teas, indicating that these active constituents may discriminate fermentation degrees effectively. By principal component analysis (PCA) and stepwise linear discriminant analysis (S-LDA), the vast majority of tea samples could be successfully differentiated according to their chemical markers. This study yielded three discriminant functions with the capacity to simultaneously discriminate the four tea categories with a 97.8% correct rate. In classification of oolong and other teas, there were one discriminant function and two equations with best discriminant capacity. Furthermore, the classification of different degrees of fermentation of oolong and external validation achieved the desired results. It is suggested that polyphenols and caffeine are the distinct variables to establish internationally recognized models of teas.

Solid-phase extraction (SPE) and direct competitive chemiluminescence enzyme immunoassay (dcCL-EIA) were combined for the detection of organophosphorus pesticides (OPs) in environmental water samples. dcCL-EIA based on horseradish peroxidase labeled with a broad-specificity monoclonal antibody against OPs was developed, and the effects of several physicochemical parameters on dcCL-EIA performance were studied. SPE was used for the pretreatment of water samples to remove interfering substances and to concentrate the OP analytes. The coupling of SPE and dcCL-EIA can detect seven OPs (parathion, coumaphos, phoxim, quinalphos, triazophos, dichlofenthion, and azinphos-ethyl) with the limit of quantitation below 0.1 ng/mL. The recoveries of OPs from spiked water samples ranged from 62.5% to 131.7% by SPE-dcCL-EIA and 69.5% to 112.3% by SPE-HPLC-MS/MS. The screening of OP residues in real-world environmental water samples by the developed SPE-dcCL-EIA and their confirmatory analysis using SPE-HPLC-MS/MS demonstrated that the assay is ideally suited as a monitoring method for OP residues prior to chromatographic analysis.