Porous Frustrated Lewis Pairs Catalyst Constructed on Defective Zirconium-Based Metal-Organic Frameworks for Hydrogenation Reactions with H2.

A porous metal-organic framework (MOF)-based frustrated Lewis pairs (FLPs) were prepared via a ligand replacement strategy to generate organic linker defects in zirconium-based MOF (MOF-808), thereby exposing Zr sites as Lewis acid. Due to the rigid features of the MOF skeleton, the unsaturated metal cluster and the adjacent lattice oxygen (Lewis bases) are in sterically hindered positions, which formed FLP sites with efficient H2 activation ability. This porous heterogeneous FLP catalyst [MOF-808-OH (15%)] exhibits high performance styrene hydrogenation to ethylbenzene with 99% yield. The high structural stability and reusability enabled the catalyst to maintain an over 98% activity after five cycles. This work provides a defect modulation strategy to prepare MOF-based solid FLP catalysts.

An antioxidant hydrogel dressing with wound pH indication function prepared based on silanized bacterial nanocellulose crosslinked with beet red pigment extract.

Maintaining wound moisture and monitoring of infection are crucial aspects of chronic wound treatment. The development of a pH-sensitive functional hydrogel dressing is an effective approach to monitor, protect, and facilitate wound healing. In this study, beet red pigment extract (BRPE) served as a native and efficient pH indicator by being grafted into silane-modified bacterial nanocellulose (BNC) to prepare a pH-sensitive wound hydrogel dressing (S-g-BNC/BRPE). FTIR confirmed the successful grafting of BRPE into the BNC matrix. The S-g-BNC/BRPE showed superior mechanical properties (0.25 MPa), swelling rate (1251 % on average), and hydrophilic properties (contact angle 21.83°). The composite exhibited a notable color change as the pH changed between 4.0 and 9.0. It appeared purple-red when the pH ranged from 4.0 to 6.0, and appeared light pink at pH 7.0 and 7.4, and appeared ginger-yellow at pH 8.0 and 9.0. Subsequently, the antioxidant activity and cytotoxicity of the composite was evaluated, its DPPH·, ABTS+, ·OH scavenging rates were 32.33 %, 19.31 %, and 30.06 %, respectively, and the cytotoxicity test clearly demonstrated the safety of the dressing. The antioxidant hydrogel dressing, fabricated with a cost-effective and easy method, not only showed excellent biocompatibility and dressing performance but could also indicated the wound state based on pH changes.

Asymmetric Total Synthesis of Alstrostine G Utilizing a Catalytic Asymmetric Desymmetrization Strategy.

A highly effective enantioselective monobenzoylation of 1,3-diols has been developed for the synthesis of 1,1-disubstituted tetrahydro-ß-carbolines. The chemistry has been successfully applied to the asymmetric total synthesis of (+)-alstrostine G, which also features a cascade Heck/hemiamination reaction enabling facile construction of the pivotal pentacyclic core.

Surficial Host-Guest Responsive CsPbBr3 Perovskite Nanocrystals for Programmable Multi-Level Information Encryption.

The design of smart stimuli-responsive photoluminescent materials capable of multi-level encryption and complex information storage is highly sought after in the current information era. Here, a novel adamantyl-capped CsPbBr3 (AD-CsPbBr3) perovskite NCs, along with its supramolecular host-guest assembly partner a modified ß-CD (mCD), mCD@AD-CsPbBr3, are designed and prepared. By dispersing these two materials in different solvents, namely, AD-CsPbBr3 in toluene, mCD@AD-CsPbBr3 in toluene, and mCD@AD-CsPbBr3 in methanol, the three solutions exhibit diverse photoluminescence (PL) turn-on/off or PL discoloration response upon supramolecular stimulus. Based on these responses, a proof-of-principle programmable Multi-Level Photoluminescence Encoding System (MPLES) is established. Three types of four-level and three types of three-level information encoding are achieved by the system. A layer-by-layer four-level information encryption and decryption as well as a two-level encrypted 3D code are successfully achieved.

Well-defined in-textile photolithography towards permeable textile electronics.

Textile-based wearable electronics have attracted intensive research interest due to their excellent flexibility and breathability inherent in the unique three-dimensional porous structures. However, one of the challenges lies in achieving highly conductive patterns with high precision and robustness without sacrificing the wearing comfort. Herein, we developed a universal and robust in-textile photolithography strategy for precise and uniform metal patterning on porous textile architectures. The as-fabricated metal patterns realized a high precision of sub-100 µm with desirable mechanical stability, washability, and permeability. Moreover, such controllable coating permeated inside the textile scaffold contributes to the significant performance enhancement of miniaturized devices and electronics integration through both sides of the textiles. As a proof-of-concept, a fully integrated in-textiles system for multiplexed sweat sensing was demonstrated. The proposed method opens up new possibilities for constructing multifunctional textile-based flexible electronics with reliable performance and wearing comfort.

Advancements in Microwave Absorption Motivated by Interdisciplinary Research.

Microwave absorption materials (MAMs) are originally developed for military purposes, but have since evolved into versatile materials with promising applications in modern technologies, including household use. Despite significant progress in bench-side research over the past decade, MAMs remain limited in their scope and have yet to be widely adopted. This review explores the history of MAMs from first-generation coatings to second-generation functional absorbers, identifies bottlenecks hindering their maturation. It also presents potential solutions such as exploring broader spatial scales, advanced characterization, introducing liquid media, utilizing novel toolbox (machine learning, ML), and proximity of lab to end-user. Additionally, it meticulously presents compelling applications of MAMs in medicine, mechanics, energy, optics, and sensing, which go beyond absorption efficiency, along with their current development status and prospects. This interdisciplinary research direction differs from previous research which primarily focused on meeting traditional requirements (i.e., thin, lightweight, wide, and strong), and can be defined as the next generation of smart absorbers. Ultimately, the effective utilization of ubiquitous electromagnetic (EM) waves, aided by third-generation MAMs, should be better aligned with future expectations.

Research Progress in Tunable Fiber Lasers Based on Multimode Interference Filters.

Tunable fiber lasers have the advantages of good beam quality, high integration, and adjustable output wavelength, and they are widely used in fields such as optical fiber communication and optical fiber sensing. The fiber filter is one of the key components of tunable fiber lasers. Among the various filters currently used, multimode interference filters have the advantages of simple structure, convenient implementation, flexible tuning methods, and convenient spectral range design. The structures of multimode interference filters based on multimode fibers, no-core fibers, multi-core fibers, tapered fibers, and other special fibers are introduced in this paper. The working principles and tuning methods are analyzed and the research progress of tunable fiber lasers based on these filters is summarized. Finally, the development trend of tunable fiber lasers based on multimode interference filters is discussed. The rapid development and applications of multimode interference filters can help improve the performance of continuous and pulse lasers as well as promote the practicality of tunable fiber lasers.

Physiological Properties of Perennial Rice Regenerating Cultivation in Two Years with Four Harvests.

Crop perennialization has garnered global attention recently due to its role in sustainable agriculture. However, there is still a lack of detailed information regarding perennial rice's regenerative characteristics and physiological mechanisms in crop ratooning systems with different rice stubble heights. In addition, the response of phytohormones to varying stubble heights and how this response influences the regenerative characteristics of ratoon rice remains poorly documented. Here, we explored the regenerative characteristics and physiological mechanisms of an annual hybrid rice, AR2640, and a perennial rice, PR25, subjected to different stubble heights (5, 10, and 15 cm). The response of phytohormones to varying stubble heights and how this response influences the regenerative characteristics of ratoon rice were also investigated. The results show that PR25 overwintered successfully and produced the highest yield, especially in the second ratoon season, mainly due to its extended growth duration, higher number of mother stems, tillers at the basal nodes, higher number of effective panicles, and heavier grain weight when subjected to lower stubble heights. Further analysis revealed that PR25 exhibited a higher regeneration rate from the lower-position nodes in the stem with lower stubble heights. this was primarily due to the higher contents of phytohormones, especially auxin (IAA) and gibberellin (GA3) at an early stage and abscisic acid (ABA) at a later stage after harvesting of the main crop. Our findings reveal how ratoon rice enhances performance based on different stubble heights, which provides valuable insights and serves as crucial references for delving deeper into cultivating high-yielding perennial rice.

Immunosenescence and cancer: Opportunities and challenges.

As individuals age, cancer becomes increasingly common. This continually rising risk can be attributed to various interconnected factors that influence the body's susceptibility to cancer. Among these factors, the accumulation of senescent cells in tissues and the subsequent decline in immune cell function and proliferative potential are collectively referred to as immunosenescence. Reduced T-cell production, changes in secretory phenotypes, increased glycolysis, and the generation of reactive oxygen species are characteristics of immunosenescence that contribute to cancer susceptibility. In the tumor microenvironment, senescent immune cells may promote the growth and spread of tumors through multiple pathways, thereby affecting the effectiveness of immunotherapy. In recent years, immunosenescence has gained increasing attention due to its critical role in tumor development. However, our understanding of how immunosenescence specifically impacts cancer immunotherapy remains limited, primarily due to the underrepresentation of elderly patients in clinical trials. Furthermore, there are several age-related intervention methods, including metformin and rapamycin, which involve genetic and pharmaceutical approaches. This article aims to elucidate the defining characteristics of immunosenescence and its impact on malignant tumors and immunotherapy. We particularly focus on the future directions of cancer treatment, exploring the complex interplay between immunosenescence, cancer, and potential interventions.

Mechanical Properties Variation in Wood-Plastic Composites with a Mixed Wood Fiber Size.

In this study, the influence of fiber particle size on the mechanical properties of a wood--plastic composite (WPC) was investigated using a combination of experimental measurements and numerical modeling. Four different sizes of wood fibers (10-20 mesh, 20-40 mesh, 40-80 mesh, and 80-120 mesh) were used to reinforce high-density polyethylene (HDPE), either separately or in combination. The different sizes of fibers produced varying properties in the resulting composites. The smallest fiber size (80-120 mesh) resulted in the lowest flexural and tensile properties, but the highest impact strength (15.79 kJ/m2) compared to the other three sizes (12.18-14.29 kJ/m2). Using a blend of fiber sizes resulted in improved mechanical properties. Composites containing a mix of 20-40 mesh and 40-80 mesh fibers exhibited the best flexural (strength 74.16 MPa, modulus 5.35 GPa) and tensile performance (strength 48.27 MPa, modulus 4.30 GPa), while composites containing a mix of all four fiber sizes had the highest impact-resistant strength (16.08 kJ/m2). Several models, including the Rule of Mixtures (ROM), the Inverse Rule of Mixtures (IROM), and the Hirsch models, were used to predict the performance of WPCs. The ROM model was found to be the most accurate in describing the mechanical properties of WPCs reinforced with multi-size wood fibers, based on the sum squared error (SSE) analysis.

A novel plasma-sprayed Ti4O7/carbon nanotubes/Al2O3 coating with bifunctional microwave application.

High-performance microwave absorption coatings are critically required in the stealth defense system of military platforms. Regrettably, just optimizing the property but neglecting the application feasibility seriously inhibits its practical application in the field of microwave absorption. To face this challenge, the Ti4O7/carbon nanotubes (CNTs)/Al2O3 coatings were successfully fabricated by a plasma-sprayed method. For the different oxygen vacancy-induced Ti4O7 coatings, the enhanced ε' and ε'' values in the frequency of X-band is due to the synergistic manipulation of conductive path, defects and interfacial polarization. The optimal reflection loss of Ti4O7/CNTs/Al2O3 sample (0 wt% CNTs) is -55.7 dB (8.9 GHz of 2.41 mm), while the electromagnetic interference shielding effectiveness of Ti4O7/CNTs/Al2O3 sample (5 wt% CNTs) increases to 20.5 dB as the enhanced electrical conductivity. In special, the flexural strength of Ti4O7/CNTs/Al2O3 coatings first increases from 48.59 MPa (0 wt% CNTs) to 67.13 MPa (2.5 wt% CNTs) and then decreases to 38.31 MPa (5 wt% CNTs), demonstrating that an appropriate amount of CNTs evenly dispersed in the Ti4O7/Al2O3 ceramic matrix can effectively play the role of CNTs as the strengthening phase of the coatings. This research will provide a strategy by tailoring synergistic effect of dielectric loss and conduction loss for oxygen vacancy-mediated Ti4O7 material to broaden the application of absorbing or shielding ceramic coatings.

Metallic Glass-Fiber Fabrics: A New Type of Flexible, Super-Lightweight, and 3D Current Collector for Lithium Batteries.

Current collectors are indispensable parts that provide electron transport and mechanical support of electrode materials in a battery. Nowadays, thin metal foils made of Cu and Al are used as current collectors of lithium batteries, but they do not contribute to the storage capacity. Therefore, decreasing the weight of current collectors can directly enhance the energy density of a battery. However, limited by the requirements of mechanical strength, it is difficult to reduce the weight of metal foils any further. Herein, a new type of current collectors made of 3D metallic glass-fiber fabrics (MGFs), which shows advantages of super-lightweight (2.9-3.2 mg cm⁻2 ), outstanding electrochemical stability for cathodes and anodes of lithium-ion and lithium-metal batteries (LMBs), fire resistance, high strength, and flexibility suitable for roll-to-roll electrode fabrication is reported. The gravimetric energy densities of lithium batteries exhibit improvements of 9-18% by only replacing the metal foils with the MGFs. In addition, MGFs are suitable for the fabrication of flexible batteries. A high-energy-density flexible lithium battery with an outstanding figure of merit of flexible battery (fbFOM ) and flexing stability is demonstrated.

Metabolic alteration of Tetrahymena thermophila exposed to CdSe/ZnS quantum dots to respond to oxidative stress and lipid damage.

CdSe/ZnS Quantum dots (QDs) are possibly released to surface water due to their extensive application. Based on their high reactivity, even small amounts of toxicant QDs will disturb water microbes and pose a risk to aquatic ecology. Here, we evaluated CdSe/ZnS QDs toxicity to Tetrahymena thermophila (T. thermophila), a model organism of the aquatic environment, and performed metabolomics experiments. Before the omics experiment was conducted, QDs were found to induce inhibition of cell proliferation, and reactive oxygen species (ROS) production along with Propidium iodide labeled cell membrane damage indicated oxidative stress stimulation. In addition, mitochondrial ultrastructure alteration of T. thermophila was also confirmed by Transmission Electron Microscope results after 48 h of exposure to QDs. Further results of metabolomics detection showed that 0.1 µg/mL QDs could disturb cell physiological and metabolic metabolism characterized by 18 significant metabolite changes, of which twelve metabolites improved and three decreased significantly compared to the control. Kyoto Encyclopedia of Genes and Genomes analysis showed that these metabolites were involved in the ATP-binding cassette transporter and purine metabolism pathways, both of which respond to ROS-induced cell membrane damage. In addition, purine metabolism weakness might also reflect mitochondrial dysfunction associated with energy metabolism and transport abnormalities. This research provides deep insight into the potential risks of quantum dots in aquatic ecosystems.

Flexible, Transparent, and Hazy Composite Cellulosic Film with Interconnected Silver Nanowire Networks for EMI Shielding and Joule Heating.

An optical transparent and hazy film with admirable flexibility, electromagnetic interference (EMI) shielding, and Joule heating performance meeting the requirements of optoelectronic devices is significantly desirable. Herein, a cellulose paper was infiltrated by epoxy resin to fabricate a transparent cellulose paper (TCP) with high transparency, optical haze, and favorable flexibility, owing to effective light scattering and mechanical enhancement of the cellulose network. Moreover, a highly connected silver nanowire (AgNW) network was constructed on the TCP substrate by the spray-coating method and appropriate thermal annealing technique to realize high electrical conductivity and favorable optical transmittance of the composite film at the same time, followed by coating of a polydimethylsiloxane (PDMS) layer for protection of the AgNW network. The obtained PDMS/AgNWs/TCP composite film features considerable optical transmittance (up to 86.8%) and haze (up to 97.7%), while satisfactory EMI shielding effectiveness (SE) (up to 39.1 dB, 8.2-12.4 GHz) as well as strong mechanical strength (higher than 41 MPa) were achieved. The coated PDMS layer prevented the AgNW network from falling off and ensured the long-term stability of the PDMS/AgNWs/TCP composite film under deformations. In addition, the multifunctional PDMS/AgNWs/TCP composite film also exhibited excellent Joule heating performance with low supplied voltages, rapid response, and sufficient stability. This work demonstrates a novel pathway to improve the performance of multifunctional transparent composite films for future advanced optoelectronic devices.

Hepatoprotective Effects of Phloridzin against Isoniazid-Rifampicin Induced Liver Injury by Regulating CYP450 and Nrf2/HO-1 Pathway in Mice.

The protective effect of phloridzin (PHL) and its potential mechanism were examined in mice with liver injury induced by isoniazid (INH) and rifampicin (RFP). The mice were randomly divided into normal control group, model group, low (80 mg/kg), medium (160 mg/kg) and high (320 mg/kg) phloridzin-treated groups. After 28 d treatment, blood and liver tissue were collected and analysed. The results revealed that PHL regulated liver function related indicators and reduced the pathological tissue damage, indicating that PHL significantly alleviated the liver injury. Furthermore, the level of CYP450 enzyme, the expression of CYP3A4, CYP2E1, heme oxygenase-1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA and protein were inhibited by PHL. These results indicated that PHL exerts a protecting effect against liver injury induced by combination of RFP and INH. The potential mechanisms may be concerned with the activation of Nrf2/HO-1 signaling pathway containing its key antioxidant enzymes and regulation of CYP3A4 and CYP2E1.

Design, synthesis and biological evaluation of 2-aminopyridine derivatives as USP7 inhibitors.

A series of novel 2-aminopyridine derivatives 1-26 have been designed and synthesized by structural modifications on a lead USP7 inhibitor, GNE6640. All the compounds were evaluated for their USP7 inhibitory activities. The results showed that most of the compounds have good USP7 inhibitory activities at the concentration of 50 µM. Among them, compounds 7, 14 and 21 are the most potential ones from each category with the IC50 values of 7.6 ± 0.1 µM, 17.0 ± 0.2 µM and 11.6 ± 0.5 µM, respectively. Compounds 7 and 21 expressed significant binding interactions with USP7 by surface plasmon resonance (SPR)-based binding assay, but both of them presented moderate antiproliferative activities against HCT116 cells. They could effectively promote MDM2 degradation, p53 stabilization and p21 gene expression in the western blot analysis.

Surface Characteristics of Thermally Modified Bamboo Fibers and Its Utilization Potential for Bamboo Plastic Composites.

Bamboo fibers are considered as a more attractive option for the reinforcement of wood plastic composites as compared to wood fiber due to its fast growth rate and good toughness. Heat treatment is an environment-friendly method of improving the integrated performance of bamboo materials. This paper highlights the heat treatment of bamboo fiber for suitable properties as reinforcements in bamboo plastic composites. The effects of vacuum heat treatment on the surface characteristics of bamboo fibers and the properties of bamboo plastic composites were analyzed by studying the chemical composition, surface elements and polarity of bamboo fiber before and after treatment, and the physical and mechanical properties of bamboo plastic composite. The results showed that after vacuum heat treatment, the bamboo fibers became darker and experienced a transition from green to red. Moreover, FTIR, XPS and contact angle analysis indicated that the hemicellulose content, the oxygen/carbon ratio and the polar component of the bamboo fiber had a decreasing trend as the treatment temperature increased. In addition, the 24 h water absorption and the 24 h thickness expansion rate of the water absorption showed a trend of first decreasing and then increasing as the treatment temperature increased, while the bending performance of bamboo plastic composite showed a trend of increasing first and then decreasing as a result of increased treatment temperature. Therefore, a combined process of vacuum heat treatment and the addition of MAPE could improve the physical and mechanical properties of bamboo plastic composites to a certain extent.

Ti3 C2 Tx /MoS2 Self-Rolling Rod-Based Foam Boosts Interfacial Polarization for Electromagnetic Wave Absorption.

Heterogeneous interface design to boost interfacial polarization has become a feasible way to realize high electromagnetic wave absorbing (EMA) performance of dielectric materials. However, interfacial polarization in simple structures such as particles, rods, and flakes is weak and usually plays a secondary role. In order to enhance the interfacial polarization and simultaneously reduce the electronic conductivity to avoid reflection of electromagnetic wave, a more rational geometric structure for dielectric materials is desired. Herein, a Ti3 C2 Tx /MoS2 self-rolling rod-based foam is proposed to realize excellent interfacial polarization and achieve high EMA performance at ultralow density. Different surface tensions of Ti3 C2 Tx and ammonium tetrathiomolybdate are utilized to induce the self-rolling of Ti3 C2 Tx sheets. The rods with a high aspect ratio not only remarkably improve the polarization loss but also are beneficial to the construction of Ti3 C2 Tx /MoS2 foam, leading to enhanced EMA capability. As a result, the effective absorption bandwidth of Ti3 C2 Tx /MoS2 foam covers the whole X band (8.2-12.4 GHz) with a density of only 0.009 g cm-3 , at a thickness of 3.3 mm. The advantages of rod structures are verified through simulations in the CST microwave studio. This work inspires the rational geometric design of micro/nanostructures for new-generation EMA materials.

An Ultrastrong and Antibacterial Silver Nanowire/Aligned Cellulose Scaffold Composite Film for Electromagnetic Interference Shielding.

Constructing multifunctional electromagnetic interference (EMI) shielding films with superior mechanical strength has sparked a lot of interest in the fields of wearable electronics. In this work, the conductive silver nanowires (AgNWs) were synthesized and impregnated into the highly aligned cellulose scaffold (CS) fabricated by wood delignification followed by hot-pressing and polydimethylsiloxane (PDMS) dipping processes to obtain the outstanding EMI shielding cellulosic film (d-AgNWs@CS-PDMS). The consecutively conductive pathway of AgNWs was constructed in the microchannels of the CS as a result of the hydrogen bonding between AgNWs and cellulose fibers, which is conducive to the reflection of incident EM waves. The higher degree of nanofiber alignment and the compact conductive network were improved by densification upon hot pressing, which endows the composite film with striking mechanical properties (maximum tensile strength of 511.8 MPa) and superb EMI shielding performance (shielding effectiveness value of 46 dB with a filler content of 21.6 wt %) at the X band (8.2-12.4 GHz). Moreover, the existence of an intensive AgNWs network and the introduction of the PDMS layer improve the hydrophobicity and antibacterial activity of the composite film, avoiding serious health concerns in the long-term wearing. These results demonstrate that the obtained d-AgNWs@CS-PDMS composite film has high potential as an EMI shielding material used for wearable devices.

Natural wood templated hierarchically cellular NbC/Pyrolytic carbon foams as Stiff, lightweight and High-Performance electromagnetic shielding materials.

Hierarchically cellular, stiff, and lightweight niobium carbide (NbC)-pyrolytic carbon (PyC) monolithic foam composites possessing excellent electromagnetic interference shielding effectiveness (EMI SE) were developed via a natural wood template-based method. Pyrolytic carbon derived from the decomposed cellulose in the wood worked as the carbon source for the growth of NbC phase, and the NbC-PyC heterogeneous nano-interface formed between the residual PyC and the freshly formed NbC. Multi-loss mechanisms (e.g. conductive loss, dipole polarization loss, and especially interface polarization loss) were established by controlling the NbC content and residual PyC phase in the NbC-PyC foams, which significantly improved the absorption capability. Compared to 28.0 dB of PyC monolith, the EMI SE of NbC-PyC foam can reach 54.8 dB when the thickness is 0.5 mm, which outperforms the other porous-based shielding materials. Due to the highly porous structure of pristine wood, the resulting NbC-PyC foam exhibited a low density of 0.48 g/cm3, which is ~ 1/16 of dense NbC (7.78 g/cm3). Generally, this work introduces innovative ideas for designing novel and advanced transition metal carbide-carbon composite materials.