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A multi-functional modifier, which could improve the mechanical and thermal performance simultaneously, is significant in composites production. Herein, inspired by the chemistry of mussel, an interfacial modifier named FPD was designed and synthesized through one simple step, which was attached by three functional groups (including catechol, N-H bond, and DOPO). Due to the innate properties of each functional group, FPD played multiple roles: adhere to the ramie fibers from catechol and cure with the epoxy resin from -NH-, an antiflaming property from DOPO, and the compatibilizer between ramie fibers and epoxy resin was also improved by changing the polarity of ramie fiber. All of the above functions can be proved by means of water contact angle (WCA), atomic force microscope (AFM), and scanning electron microscopy (SEM), etc. After solidification, the ramie fiber/epoxy composites demonstrated superior performances in terms of good mechanical properties and excellent flame retardant property. With the addition of 30 wt.% FPD, the tensile strength and modulus of the ramie/epoxy composite showed an improvement of 37.1% and 60.9%, and flexural strength and modulus of the composite were improved by 8.9% and 19.3% comparing with no addition composite. Moreover, the composite could achieve the goal for V-0 rating in the UL-94 test and LOI value was 34.6% when the addition of FPD reached 30 wt.%. This work provided us with an efficient method for fabricating nature fiber/epoxy composites with good properties. [ABSTRACT FROM AUTHOR]

• A benzoxazine monomer with intrinsic high emissivity and solar absorptivity was synthesized. • The laser-induced superhydrophilic porous graphene enables anti-gravity water transport. • The switchable mode could achieve solar-driven desalination and passive cooling dew collection. • A high desalination efficiency of 90.9 % and 68.36 g/m−2(−|-) day−1 dew collection was realized. The importance of clean water resources for human health and economic development cannot be overlooked. Providing a way for fully passive all-day freshwater harvesting presents a significant challenge. Herein, we propose a strategy for all-day freshwater harvesting passively through a freestanding Janus film which combining solar-driven interfacial desalination during day time and dew water generation driven by passive radiative cooling at night. Specifically, the core of the strategy was a new bio-based benzoxazine which containing high-infrared emittance in the atmospheric window and the resultant cured black freestanding film owns a steady high light absorbance in the whole range of the solar irradiation wavelength. The home-made device made by the Janus film achieved a drinkable freshwater collection efficiency of 90.9 % when desalinating seawater under 1 sun illumination and achieved a dew water collection rate of 68.36 g m−2 day−1 at night. Moreover, the film has an excellent antibacterial effect, which ensures the quality of water collection and enhances the service life. Combining the advantages of bio-based raw materials, a simple fabrication process and scalability of the film, the all-day freshwater collection system makes a promising solution to alleviate freshwater shortage in many arid regions, islands and even boats sailing on the sea. [ABSTRACT FROM AUTHOR]

Energy efficiency and resource utilization are considered to be necessary for sustainable development. Organic phase change materials (PCMs) as an effective thermal energy storage tool have attracted great interest, but non-renewable ingredients, low stability and their unsafe nature largely restrict their sustainability. Herein, a series of bio-based benzoxazine-derived PCMs were developed, in which green preparation, efficient energy conversion, and safe utilization can be simultaneously achieved. Through the Mannich condensation reaction, novel PCMs can be easily synthesized with good yield and high atom economy by combining natural 3-pentadecylphenol (a cardanol derivative) and amine sources. The resulting PCMs exhibited adjustable latent heat (48.78–147.02 J g−1) by altering raw materials, which are close to their commercial unsustainable counterparts. As an example, C-aa-12 also showed considerable recycling ability after 100 times repeated use. In addition, due to the designed structure, as-prepared PCMs also possessed more excellent properties of thermal stability (Td50% was increased by 65.1%) and flame retardancy (HRR was reduced by 39.4%) compared with traditional ones, making them promising in a wider application field. [ABSTRACT FROM AUTHOR]

Background: Emerging evidence has shown that intra-tumor immune features are associated with response to immune checkpoint blockade (ICB) therapy. Accordingly, patient stratification is needed for identifying target patients and designing strategies to improve the efficacy of ICB therapy. We aimed to depict the specific immune features of patients with pancreatic cancer and explore the implication of immune diversity in prognostic prediction and individualized immunotherapy. Methods: From transcriptional profiles of 383 tumor samples in TCGA, ICGC, and GEO database, robust immune subtypes which had different response immunotherapy, including ICB therapy, were identified by consensus clustering with five gene modules. DEGs analysis and tumor microarray were used to screen and demonstrate potential targets for improving ICB therapy. Results: Three subtypes of pancreatic cancer, namely cluster 1–3 (C1–C3), characterized with distinct immune features and prognosis, were generated. Of that, subtype C1 was an immune-cold type in lack of immune regulators, subtype C2, with an immunosuppression-dominated phenotype characterized by robust TGFβ signaling and stromal reaction, showed the worst prognosis, subtype C3 was an immune-hot type, with massive immune cell infiltration and in abundance of immune regulators. The disparity of immune features uncovered the discrepant applicability of anti-PD-1/PD-L1 therapy and potential sensitivity to other alternative immunotherapy for each subtype. Patients in C3 were more suitable for anti-PD-1/PD-L1 therapy, while patients in the other two clusters may need combined strategies targeted on other immune checkpoints or oncogenic pathways. A promising target for improving anti-PD-1/PD-L1 treatment, TGM2, was screened out and its role in the regulation of PD-L1 was investigated for the first time. Conclusion: Collectively, immune features of pancreatic cancer contribute to distinct immunosuppressive mechanisms that are responsible for individualized immunotherapy. Despite pancreatic cancer being considered as a poor immunogenic cancer type, the derived immune subtypes may have implications in tailored designing of immunotherapy for the patients. TGM2 has potential synergistic roles with ICB therapy. [ABSTRACT FROM AUTHOR]

The intelligent harvesting technology for jujube leaf branches presents a novel avenue for enhancing both the quantity and quality of jujube leaf tea, whereas the precise detection technology for jujube leaf branches emerges as a pivotal factor constraining its development. The precise identification and localization of jujube leaf branches using real-time object detection technology are crucial steps toward achieving intelligent harvesting. When integrated into real-world scenarios, issues such as the background noise introduced by tags, occlusions, and variations in jujube leaf morphology constrain the accuracy of detection and the precision of localization. To address these issues, we describe a jujube leaf branch object detection network based on YOLOv7. First, the Polarized Self-Attention module is embedded into the convolutional layer, and the Gather-Excite module is embedded into the concat layer to incorporate spatial information, thus achieving the suppression of irrelevant information such as background noise. Second, we incorporate implicit knowledge into the Efficient Decoupled Head and replace the original detection head, enhancing the network's capability to extract deep features. Third, to address the issue of imbalanced jujube leaf samples, we employ Focal-EIoU as the bounding box loss function to expedite the regression prediction and enhance the localization accuracy of the model's bounding boxes. Experiments show that the precision of our model is 85%, which is increased by 3.5% compared to that of YOLOv7-tiny. The mAP@0.5 value is 83.7%. Our model's recognition rate, recall and mean average precision are superior to those of other models. Our method could provide technical support for yield estimation in the intelligent management of jujube orchards. [ABSTRACT FROM AUTHOR]

Micro-nano encapsulation strategy combining three-dimensional (3D) porous carriers and phase change materials (PCMs) has been widely investigated due to its structure stability, high efficiency, and designability. However, the current 3D scaffolds suffering from structure regularity are hard to meet the urgent requirements of high energy conversion efficiency and versatile applications. Herein, a 3D porous graphene scaffold (2LrGO@LIG), which is fabricated from polybenzoxazine/graphene oxide (GO) composite using laser irradiation that structurally engineers a gully-shaped surface and a 3D overlapped graphene networks, was employed for PCMs encapsulation. The addition of GO is proved to enhance the quality of produced laser induced graphene (LIG), which could also be reduced into laser-reduced graphene oxide (LrGO) and connect the adjacent LIGs as thermal bridges. As a consequence, the obtained phase change composite (2LrGO@LIG/MA) showed photo-thermal and electro-thermal conversion efficiency of 94.1 % and 99.1 %, respectively. In addition, benefiting from the surface hydrophobicity (135°), high energy storage density (167.7 J/g) and electrical conductivity (307.9 S/m), 2LrGO@LIG/MA also demonstrated great potential in smart building materials and wearable electronic devices. This study provides a facile method for designing advanced PCM composites with multi-energy conversion capacity and application versatility. [Display omitted] • A 3D porous graphene scaffold with a gully-shaped surface and enhanced networks is employed for PCMs encapsulation. • In-situ reduced LrGO connects adjacent LIG sheets and improves LIG quality. • A high energy density (167.7 J/g) and extraordinary solar-/electro-thermal conversion efficiencies (94.1 % and 99.1 %) are realized. • 2LrGO@LIG/MA with self-cleaning and EMI shielding abilities exhibits potential applications in construction materials and wearable electronic devices. [ABSTRACT FROM AUTHOR]

Abstract A chitin-fastening Ag@AgCl composite film with decontamination properties was successfully prepared by one-step coagulation method of the chitin- LiCl/Dimethyl Acetamide (DMAc) solution with AgNO 3. In this process, AgCl was formed in a chitin solution with the addition of AgNO 3 solution, and with the help of excess Cl− a solution of AgCl was formed. AgCl nanocrystals embedded on the surface of chitin were obtained after the solution was put into coagulation bath. The AgCl nano-crystals embedded on the surface of chitin film could be partly transformed into the Ag@AgCl by appropriate visible-light irradiation in the air. In order to explore the morphology and the formation mechanism of the composites, the well-prepared films were characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), X-ray photo-electron spectroscopy (XPS), thermogravimetric analysis (TGA), ultraviolet spectro-photometry and UV–visible absorption spectrum. The decontamination ability and recyclability of composite film was evaluated by the degradation rate of methyl orange (MO) in recycling process. By comparison, the Ag@AgCl fastened in chitin matrix was more stable than fastened by cellulose matrix. Its photo-degradation efficiency could be still retained up to 95% after 5-cycle testing. Meanwhile, the composite film could be also kept excellent mechanical properties. This work provided a simple pathway to construct the functional chitin film which could be applied as a kind of stable recycling decontamination materials. [ABSTRACT FROM AUTHOR]

Cellular demise is a pivotal event in both developmental processes and disease states, with mitochondrial regulation playing an essential role. Traditionally, cell death was categorized into distinct types, considered to be linear and mutually exclusive pathways. However, the current understanding has evolved to recognize the complex and interconnected mechanisms of cell death, especially within apoptosis, pyroptosis, and necroptosis. Apoptosis, pyroptosis, and necroptosis are governed by intricate molecular pathways, with mitochondria acting as central decision-makers in steering cells towards either apoptosis or pyroptosis through various mediators. The choice between apoptosis and necroptosis is often determined by mitochondrial signaling and is orchestrated by specific proteins. The molecular dialogue and the regulatory influence of mitochondria within these cell death pathways are critical research areas. Comprehending the shared elements and the interplay between these death modalities is crucial for unraveling the complexities of cellular demise. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fully recyclable TIM with high thermal conductivity and conformability to the rough surface was prepared. • Filled BN could be oriented by hot-pressing and led to a thermal conductivity of 3.85 W·m−1·K−1, 4.3 times higher than the composite before hot-pressing treatment. • BN recovery rate of 96.2% and other organic raw materials recovery rate of 73.6% to 82.4% were achieved. • The electronic device made of the prepared composite exhibited a 20 °C lower core temperature than the commercial silicone material. Thermal interface materials (TIMs) with excellent heat dissipation capacity are highly desired for the development of miniaturized, integrated, and dense electronic devices. In addition, with the increasing accumulation of e-waste, the recyclability of TIMs has also become an urgent concern. Herein, a fully recyclable TIM with high thermal conductivity and conformability to the rough surface was prepared based on the synthesized epoxy vitrimer and boron nitride (BN) nanosheet. Results revealed that only by simple hot-pressing, the filled BN could be easily oriented in the plane and led to a thermal conductivity of 3.85 W m−1 K−1 with the BN content of 40 wt%, which was 30 times higher than that of the pristine epoxy resin and 4.3 times higher than the composite before hot-pressing treatment. The electronic device made of the prepared composite exhibited a 20 °C lower core temperature than the commercial silicone material, due to the superior thermal conduction and mechanical compliance. Moreover, benefiting from the multistage degradation mechanism of the synthesized epoxy vitrimer, the fabricated composite could be efficiently chemically recovered under mild conditions, demonstrating the BN recovery rate of 96.2% and other organic raw materials recovery rate of 73.6% to 82.4%. This work provides us with a new strategy for the design of recyclable and high-performance TIMs. [ABSTRACT FROM AUTHOR]

This paper aimed to restrain the processing defects of aluminum alloy honeycombs using in aerospace with low stiffness and thin-walled, such as burr and collapse edge. The honeycomb material was treated by new method named ice fixation, and a CNC milling machine was used for a series of cryogenic machining. The fixation strength was calculated and machining defect reasons were analyzed. The cryogenic milling mechanism with ice fixation was established at the same time. Results show that compared to the without ice or conventional fixation way, the honeycomb fixation force and strength are all greatly increasing and that can reach 287 N and 19.1 kPa, respectively. Meanwhile, the processing defects are effectively suppressed. Others the cutting depth has greater influence on surface quality, and it makes the milling force improved three times, while the improvement of fixation and milling force and the cryogenic processing are the main reasons of reducing defects. The ice fixation cryogenic processing provides a new and effective method for aluminum alloy honeycomb with low rigidity and thin-wall. [ABSTRACT FROM AUTHOR]

This paper is aimed to restrain the defects such as fluff and ablation, which were often found in machining of the aramid fiber-reinforced composites (AFRP). The cooling method of spray liquid nitrogen was adopted in the orthogonal milling process. The processing parameters including cutting depth, cutting speed, cooling temperature, feed speed, and liquid nitrogen flow were considered in details, and their effects on the processing quality were researched and analyzed. The analysis optimization methods of processing parameter were employed for the influence on the machining surface quality. Meanwhile, the optimal machining surface quality was predicted and verified. The results show that the cryogenic way realizes a bigger improved role on machining quality than the conventional one for AFRP. As well as the influence order of processing parameters on the roughness is cutting depth, cutting speed, cooling temperature, feed speed, and liquid nitrogen flow. And the predicted result Ra = 0.557 μm of minimum surface roughness value is similar with the actual one Ra = 0.572 μm and verifies the feasibility of optimization method. For processing of AFRP, the cooling way of spray liquid nitrogen has a positive role with high quality and efficiency. [ABSTRACT FROM AUTHOR]

This paper presents comprehensive investigation on the nickel-base alloy material used in the aerospace with difficult machining whose cutting tool is worn failure quickly. The reason mainly relates to the high temperature of cutting zone. The cryogenic cooling method was adopted for a series of machining experiments. Based on the entropy production of the cutting system, the entropy productions of diffusion, adhesion, and oxidation wear of tool were calculated under different cutting speeds. And the wear mechanism was explained through the self-organization characteristics of cutting friction and wear system. The results indicate that with the increase of cutting speed, it has the greater entropy production. To traditional cutting, at the 132 m/min speed, the entropy production has not had the decreased stage with time, and the tool self-organizing has not played a role. However, in cryogenic cooling environment, when the speed is 220 m/min, the cutting tool's self-organization is still in effect, and its service life can be significantly extended more than three times. Compared with the traditional processing, the cryogenic one is more likely to form a self-organization dissipative structure and obviously improves the cutting speed which the self-organization can play a role. Furthermore, it also increases the cutting effect with the best processing efficiency. [ABSTRACT FROM AUTHOR]

The combination of photothermal components and phase change materials (PCMs) has received extensive attention. However, the incorporation of photothermal functionality into PCMs confronts the fatal problems of low utilization efficiency and performance compromise during processing. In this work, an acrylate monomer-passivation strategy was proposed to wrap photosensitive black phosphorus nanosheets (CG-BPs) to retain their intrinsic properties for high photothermal conversion efficiency. In addition, a flame-retardant acrylate (MCBDB) was further synthesized to crosslink with CG-BPs and build a framework for PEG1000 encapsulation. The resulting composite (cPCMs-1.2) was able to achieve a photothermal conversion efficiency of 85.3% even with a low content of CG-BPs (1.2 wt%) and unconcentrated irradiation. And benefiting from the synergistic flame-retardancy of CG-BPs and poly(MCBDB), the PCM composites displayed a reduced peak heat release rate of 38.7% compared with that of pristine PEG1000, indicating improved fire resistance. Considering its appropriate phase-change temperature, the application demonstration of the fabricated cPCMs-1.2 for human body hot compress was conducted, in which the promoting effect on blood circulation was observed. This work provides us with a new idea for the simple fabrication and new application of photothermal PCM with high photothermal conversion efficiency and application safety. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D porous laser-induced graphene supporting matrix with plant leaf-mimetic network (PLMN) for loading phase change materials (PCMs) was fabricated. • Vein-like LIG is responsible for efficient energy harvesting as well as fast heat flow transport and mesophyll-like LIG is for high encapsulation of polyethylene glycol. • The plant leaf-mimetic composite (PLMC) exhibit a large latent heat of 162.3 J/g and high thermal conductivity of 1.18 W/m·K (391.67% increment than pure PEG). • The resin layer provides mechanical support and flame-retardant function, ensuring the use safety of PLMC. To achieve efficient energy harvesting and utilization, phase change composites (PCCs) with high energy storage density, thermal conductivity, and photothermal conversion ability have always been a research focus. Herein, a three-dimensional (3D) porous laser-induced graphene supporting matrix with the plant leaf-mimetic network (PLMN) for loading phase change materials (PCMs) was fabricated by direct laser writing on polybenzoxazine resin (Poly(PH-ddm)). PLMN is designed to consist of laser-induced graphene (LIG) with both vein-like and mesophyll-like structures, the former one mainly responsible for efficient energy harvesting as well as fast heat flow transport and the latter one as the dominant part for high encapsulation of polyethylene glycol (PEG) PCM. The obtained plant leaf-mimetic composite (PLMC) exhibits a large latent heat of 162.3 J/g and high thermal conductivity of 1.18 W/m·K (391.67 % increment than pure PEG). PLMC also shows a high solar energy conversion efficiency of 84.1 %, which benefits from the well-designed PLMN structure as well as the thermal insulation effect of the resin layer. In addition, the resin layer provides mechanical support and flame-retardant function, ensuring the use safety of PLMC. The applications of PLMC for efficient utilization of solar energy and thermal management of electronics have been well-demonstrated. This work provides novel insights into the design and fabrication of PCCs with great potential in solar energy utilization and other thermal energy-related processes. [ABSTRACT FROM AUTHOR]

The uniform distribution of hydrophilic two-dimensional nanosheets in hydrophobic polymeric matrix and strong interfacial interaction between them are of great significance for the fabrication of composites, but challenging. In this work, an easily-operating strategy to prepare Ti 3 C 2 T x MXene/polybenzoxazine (PBZ) composites with homogeneous dispersion and enhanced comprehensive properties is reported, in which the rich polar groups on MXene surface and purposefully constructed hydrogen bonds (H-bonds) play crucial roles. Specifically, the oxygen and fluorine-containing terminations on Ti 3 C 2 T x MXene surface were increased by varied etching conditions. Then, the composites were prepared by solvent-assisted drop-casting and annealing method. The H-bonds between MXene and benzoxazine can not only accelerate the ring-opening polymerization, but also enhance their interfacial interactions. Accordingly, the obtained composites exhibited excellent comprehensive properties, showing the enhancement in tensile strength of 22.1%, impact strength of 50%, and thermal conductivity of 67.3% when the filler content was only 2 wt%. This study provides us a H-bonds assisted method to disperse hydrophilic nanosheets in hydrophobic polymeric matrix for the fabrication of nanocomposites with enhanced properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two high purity bio-based isomeric benzoxazine resins are synthesized. • The benzoxazine isomers shows different crystallization efficiency and crystals. • Distinct cross-linking networks and H-bonds are obseved in cured resins. • The leverage of short-chain alkyl groups on benzoxazine chemistry is revealed. Bio-based feedstocks usually contain many isomers with similar structures, and the short alkyl substituents are generally considered as low-reactive groups in benzoxazine chemistry due to their low induction effect and chemical inertness. Therefore, little attention has been paid on their effects on the synthesis or properties of benzoxazine. In this work, two bio-based benzoxazine isomers (CAR-fbz and THY-fbz) containing methyl and isopropyl groups with interchanged positions were synthesized from the renewable carvacrol and thymol. Their synthetic process, crystal features, and curing reactions were carefully investigated. Results showed that different side reacitions and by-products were detected under the same synthese conditions. And using the similar purification method, CAR-fbz and THY-fbz with high purity were found to have different crystal features. In addition, the cured systems also indicated varied H-bonding features and thermal properties based on differential scanning calorimetric (DSC) and thermogravimetric analysis (TGA) results. With the help of density functional theory (DFT) calculation, the reasons were attributed to the different electrophilicity of phenol moiety, varied molecular symmetry and intermolecular interaction caused by the overlooked short alkyls. Summarily, the leverage of short-chain alkyl groups on benzoxazine chemistry is revealed. The result is significant for the benzoxazine synthesis, especially when the renewable compounds are taken as the starting materials for bio-based benzoxazine preparation, which often has many isomers with similar structures. [ABSTRACT FROM AUTHOR]

When artificially introducing an ortho -amide group into benzoxazine monomer, the conversion of polybenzoxazine (PBZ) into polybenzoxazole (PBO) could happen at higher temperature. However, the mechanism investigation for this reaction is far from enough, which is very significant for the PBO fabrication from PBZ. In this work, we designed three kinds of benzoxazines (PIC-abz, 4-MEP-abz and 6-MEP-abz) containing both pyridyl and amide group with similar structures. The existence of intramolecular N–H⋯N H-bonding involved with amide group and the N atom in pyridine ring, as well as the N–H⋯O H-bonding between the amide N–H and the O atom in oxazine ring, were confirmed by 1H–1H nuclear overhauled effect spectroscopy (NOESY) and concentration dependent 1H NMR spectra. In addition, the respective strength of these H-bonding in different precursors was calculated by non-covalent interaction (NCI) simulation. Results showed that besides the performance of resulted PBZ, the conversion temperature of PBZ into PBO was significantly influenced by the N–H⋯N hydrogen bonding involved with pyridyl and amide groups. Based on which, the mechanism of PBO formation was proposed and systematically investigated. The outcome of this work will help us to obtain PBO in a more efficient and reasonable manner starting from PBZ. [Display omitted] • Benzoxazine monomers containing both pyridyl and amide groups with similar structures were designed. • The role of NH hydrogen bonding to the oxazine O atom with respect to the ease of ring opening has been supported. • The role of hydrogen bonding to the PBZ-PBO transformation has been explained. • Mechanism regarding intramolecular cyclization related to H-bonding strength was proposed. [ABSTRACT FROM AUTHOR]

In polymer science and industry, the important role of thermosetting resin is well-recognized. However, most thermosets suffer from the overdependence on petroleum resource and in addition are linked to environmental concerns. The development of sustainable thermosetting resins thus has become an objective of contemporary research. Addressing this need generally requires renewable feedstocks, satisfied comprehensive properties, and long service life or recyclability. Herein, a systematic overview regarding recent advances in sustainable thermosetting resins is provided. Firstly, the origins and access of bio-based platform compounds successfully applied in the bio-based thermosetting resins are being discussed. Subsequently, the synthesis, structure-property relationships, and methodologies for the functionalization of three typical bio-based thermosets, including benzoxazine, epoxy resin and unsaturated polyester, are being reviewed. Finally, strategies for the recycling of bio-based thermoset waste products are being presented. The objective of this work is not only to summarize the recent progress on sustainable thermosets, but also help us understand them more deeply and widely in a short time, so as to promote their faster development. Image, graphical abstract [ABSTRACT FROM AUTHOR]

With the purpose to obtain an eco-friendly flame retardant for epoxy resin, a facile method for the synthesis of a bio-based epoxy monomer containing DOPO units (DGEBDB) from lignin-derived vanillin and guaiacol, was presented in this work. During the synthesis process, guaiacol acted as both reactant and solvent. And it could be recycled in situ and re-used as the fresh one. In order to evaluate the flame retardancy of DGEBDB, it was mixed with diglycidyl ether of bisphenol A (DGEBA) and cured with 4,4-diaminodiphenylmethane (DDM). Results showed that, DGEBDB demonstrated a good compatibility with DGEBA, and the mechanical properties of cured resins were obviously improved with the addition of DGEBDB. As expected, the limiting oxygen index (LOI) of cured resin reached 30.2% with the content of phosphorus only 0.67 wt%, in which the weight ratio between DGEBDB and DGEBA was 1:9 (B1D9/DDM). When the weight ratio of DGEBDB to DGEBA was further increased to 2:8 for the B2D8/DDM system, the UL-94 V-0 grade was achieved. Meanwhile, the mechanism of DGEBDB in improving the flame retardancy of cured resin was discussed and revealed. This easily available and eco-friendly DGEBDB was proved to be a highly efficient reactive flame retardant for epoxy resin. • A high-efficient flame retardant for epoxy was synthesized from the renewable resource. • Guaiacol acted as both reactant and solvent, it could be recycled and re-used. • The flame retardant showed very good compatibility with DGEBA. • UL-94 V0 grade epoxy was achieved with the phosphorus content was only 1.27%. [ABSTRACT FROM AUTHOR]

A new strategy for the property regulation of polybenzoxazine via the regiochemistry of amide substituents was reported in this work. After the benzoxazine isomers, 2,6BAP-abz and 3,5BAP-abz, were synthesized, their chemical structures were confirmed by NMR, FT-IR and MS spectra. Then, how does the regiochemistry of amide substituent regulate the curing behaviors of benzoxazine monomers, as well as the thermal properties and flame retardancy of cured resins, poly(2,6BAP-abz) and poly(3,5BAP-abz), were investigated. Results showed that the intramolecular H-bonding involved with the ortho-CON H and O in oxazine ring in 3,5BAP-abz was much stronger than that in 2,6BAP-abz, which was responsible for its higher curing reactivity. As for the cured resin, poly(2,6BAP-abz) demonstrated higher glass transition temperature (T g) and lower surface free energy (SFE) due to the formation of more intramolecular N–H⋯N interaction between pyridine and ortho-CON H . In addition, this H-bonding was also related with the oxazole ring formation temperature and fire retardancy of poly(2,6BAP-abz) and poly(3,5BAP-abz). Overall, a deeper insight into the effect of regiochemistry on properties of polybenzoxazine was achieved. Image 1 • Selective formation of inter- or intramolecular H-bonding in PBZ was achieved through the benzoxazine isomers design. • Manipulation on the regiochemistry of amide substituent and its effect on the properties of PBZ were investigated. • It is the first time the effect of H-bonding on the polybenzoxazole formation temperature from o-amide PBZ was reported. • H-bonding was proved to have relationship with the fire resistance of o-amide PBZ due to the formation of polybenzoxazole. [ABSTRACT FROM AUTHOR]

Background: CD58 has been demonstrated to be abnormally expressed in multiple hematopoietic malignancies and solid tumors and plays an essential role in tumorigenesis and progression; however, its clinical significance and prognostic value in pancreatic ductal adenocarcinoma (PDAC) remain unknown. Methods: Based on diverse online public databases and 81 PDAC samples of tissue microarray-based immunohistochemistry (IHC), we evaluated CD58 expression in PDAC patients and analyzed its association with clinicopathological characteristics, clinical outcomes, and infiltration of immune cells in PDAC. Furthermore, the correlation between CD58 and the cancer stem cell (CSC)-related, epithelial–mesenchymal transition (EMT)-related, and immune-related markers were detected. Besides, the functional enrichment analysis and related pathways were analyzed and visualized. Results: CD58 expression was elevated in pancreatitis and PDAC tissues than normal pancreas or adjacent nontumor tissues. The positive cases of CD58 (e.g. more than 50% positive cells) in PDAC account for 95.06% (77/81). Upregulated CD58 in cancer tissues was associated with worse histological grade, larger tumor size, and poorer overall survival and disease-free survival in PDAC patients. Furthermore, Cox multivariate regression analysis revealed that CD58 was an independent prognostic factor in PDAC. CD58 expression was correlated with infiltrations of neutrophils, CD8+ T cells, and dendritic cells (DCs). In addition, correlation gene analysis indicated that CD58 expression was strongly correlated with immune-related, EMT-related, and CSC-related markers. Functional enrichment analysis and KEGG pathway manifested that CD58 might be involved in PDAC initiation and progression. Conclusions: CD58 expression is upregulated in PDAC tissues and its high expression is notably related to poor survival of PDAC. Therefore, CD58 may serve as a novel and effective marker for predicting the prognosis of PDAC patients. [ABSTRACT FROM AUTHOR]

This paper presents the first comprehensive investigation on the serious problems of tool wear and service life in conventional milling nickel-based superalloy. A series of machining experiments were conducted at various combinations of cutting parameters in conventional and cryogenic at 77-K milling processes. The morphology and element compositions of tool processing surfaces were analyzed and measured by the scanning electron microscopy and an energy-dispersive spectrometer, respectively. Meanwhile, the carbide tool wear behavior and mechanism in cryogenic cooling condition were also discussed in detail. The new findings indicate that at low cutting speed, the adhesive wear is easily found for the conventional machining, and the oxidation wear is for the high speed. As well as the cutting depth and feed speed are all limited, that is, lower machining efficiency. In liquid nitrogen cryogenic condition, the tool wear is not apparent at low and medium speeds, so that we can choose larger cutting depth and feed speed. At high speed, a part of adhesion and diffusion wears can be found, that is, inconspicuous oxidative wear, and the chip already made the plastic change. Furthermore, the tool service life can be increased four times at high speed and the processing efficiency is also improved obviously. The use of the liquid nitrogen cryogenic processing method can effectively solve the problems of serious tool wear and the lower processing efficiency for the nickel-based superalloy. [ABSTRACT FROM AUTHOR]

Pancreatic cancer is distinguished by an immunosuppressive tumor microenvironment (TME) that facilitates cancer progression. The assembly of the TME involves numerous contributing factors. Migrasomes, recently identified as cellular organelles in migrating cells, play a pivotal role in intercellular signaling. However, research into their involvement in cancers remains nascent. Thus far, whether pancreatic cancer cells generate migrasomes and their potential role in TME formation remains unexplored. In this study, it was found that both murine and human pancreatic cancer cells could indeed generate migrasomes, termed pancreatic cancer cell-derived migrasomes (PCDMs), which actively promote cancer progression. Moreover, utilizing chemokine antibody arrays and quantitative mass spectrometry analysis, we observed significant differences between the chemokines, cytokines, and proteins present in PCDMs compared to their originating cell bodies. Notably, PCDMs exhibited an enrichment of immunosuppression-inducing factors. Furthermore, macrophages could directly uptake PCDMs, leading to the expression of high levels of M2-like markers and secretion of tumor-promoting factors. PCDM-induced macrophages played a pivotal role in inhibiting T cell proliferation and activation partially through ARG-1. In summary, this study provides compelling evidence that pancreatic cancer cells generate migrasomes, which play a crucial role in promoting tumor progression by contributing to an immunosuppressive TME. The exploration of migrasomes as a therapeutic target could pave the way for the development of tailored immunotherapies for pancreatic cancer. • Pancreatic cancer cells can generate migrasomes, which actively induce the recruitment of macrophages. • Pancreatic cancer cell-derived migrasomes (PCDMs) are enriched with chemokines and cytokines. • PCDM-educate macrophages promote cancer progression by fostering an immunosuppressive TME. • These novel findings provide new directions to explore innovative immunotherapy approaches for various cancers. [ABSTRACT FROM AUTHOR]

Abstract: Recently, growing attention has been paid to the accurate determination of fluoride anion (F−) in the environment and living systems for its toxicity and biological function investigation. In this paper, we developed a ratiometric visual and red-emitting fluorescent dual-channel probe (1) employed Si–O bond as a highly selective recognition receptor for imaging F− in living cells. Probe 1 possesses a potential internal charge transfer (ICT) structure, and displays a large (158nm) red-shifted absorption spectrum and the color changes from yellow to blue upon addition of F− in the aqueous solution. In addition, probe 1 can be used to detect F− quantitatively by the ratiometric absorption and turn-on fluorescence spectroscopy methods with excellent sensitivity. Finally, the results of its application to bioimaging of F− in living cells show that probe 1 would be of great benefit to biomedical researchers for investigating the effects of fluoride in biological systems. [Copyright &y& Elsevier]

Pancreatic cancer is an inflammatory malignancy, and tumor-associated macrophages (TAMs) are the predominant inflammatory cells in tumor tissue. TAMs have complicated interactions with pancreatic cancer cells, however, the details and mechanisms remain largely unknown. In this study, transcriptomics and proteomics analyses were performed to explore the interactions between murine pancreatic cancer cells and TAMs. Dopamine (DA) has been reported to suppress inflammations. However, its roles in TAMs of pancreatic cancer have not been reported. Herein, the roles and mechanisms of DA to affect the chemotherapeutic efficacy for pancreatic cancer were studied. Multi-omics results revealed that there was a tumor-promoting vicious cycle involving murine pancreatic cancer cells and TAMs. DA substantially improved the chemotherapeutic efficacy both in vitro study and in immunocompetent murine pancreatic cancer models by suppression of the M2 characters of TAMs. Further studies found that activation of DRD4 by DA led to the decrease of cAMP, and then inhibited the activation of PKA/p38 signal pathway, which suppressed the tumor-promoting inflammation of TAMs. This study uncovers the reciprocal interactions between TAMs and pancreatic cancer cells using multi-omics techniques and presents that DA has synergistic roles with chemotherapy for pancreatic cancer by suppressing of TAM-derived inflammations. [ABSTRACT FROM AUTHOR]

The interactions between tumor immune microenvironment (TIME) and pancreatic cancer cells can affect chemotherapeutic efficacy; however, the mechanisms still remain largely unknown. Thirty items in TIME were comprehensively screened by using tissue microarray from pancreatic cancer patients. Their expressions, interconnections and predictive roles for survival were analyzed. Twenty-one of 30 items could stratify the survival of the patients; however, multivariate analysis found that only 5 independent risk factors could predict worse survival (M2-polarized tumor-associated macrophages (TAMs), IgG4 positive cells, TGF-β1, GM-CSF and lymphangiogenesis). They had a much higher expression levels in tumoral tissue, compared to peritumoral tissue. The Spearman analysis showed that M2-polarized TAM, TGF-β1 and GM-CSF were positively correlated with pancreatic cancer stem cells (PCSC), angiogenesis and lymphangiogenesis. Both human and murine pancreatic cancer cells could induce M2-polarized TAM, which showed substantial roles to decease chemotherapeutic effects. After treated by gemcitabine, both human and murine pancreatic cancer cell lines expressed higher level of immune check points, PCSC markers and varieties of immunosuppressive factors; however, TGF-β1 and GM-CSF had the highest increase. Based on the above results, TGF-β1 and GM-CSF were proposed to be the optimal potential targets to improve chemotherapeutic effects. In immunocompetent murine models, we demonstrated that combined blockade of TGF-β1 and GM-CSF improved the chemotherapeutic effects by inhibition of M2-polarized TAM and induction of CD8 positive T cells. This study presents a novel promising combined strategy to improve the chemotherapeutic effects for pancreatic cancer. [ABSTRACT FROM AUTHOR]

Blending with flame retardants or introducing fire resistant elements into their skeletons is a routine method to obtain the fire resistant epoxy resins. Herein, we report a novel epoxy monomer diglycidyl ether of genistein (DGEG) synthesized from the renewable genistein, and after it was cured with 4, 4-diaminodiphenylmethane (DDM), the intrinsically flame-retardant resin (DGEG/DDM), which contains only C, H and O elements, was obtained. The DGEG/DDM system demonstrates a total heat release (THR) as low as 6.3 kJ/g measured by microscale combustion calorimetry (MCC), a high limiting oxygen index (LOI) of 33.1%, and the flammability rating of V-0 in UL94 test. In addition, when compared with the bisphenol A epoxy resin system (DER332/DDM) cured under the same condition, DGEG/DDM exhibits higher glass transition temperature (223 °C vs. 175 °C) and shows a 12%, 19%, 33% and 183% increment in storage modulus (25 °C), tensile strength, flexural strength and residual char value at 800 °C, respectively. The results in this work provide us a new strategy to synthesize high performance flame retardant epoxy resins by taking advantages of the unique structures of renewable compounds. Image 1 [ABSTRACT FROM AUTHOR]

Design and development of a high power, widebandwidth W-band travelling wave tube (TWT) is presented in this paper. The design and simulation covers folded waveguide (FWG) circuit, electron gun, periodical permanent magnet system, and coupling window with the emphasis on the FWG optimization and particle-in-cell simulation by Computer Simulation Technology (CST) particle studio. Two TWT prototypes have been developed and tested, which demonstrate over 30-W output power in frequency between 91 and 101 GHz with over 30-dB saturated gain. Maximum power was found to be about 40 W around 95 GHz, while the flat output power curve under same drive level was observed. [ABSTRACT FROM PUBLISHER]

W-band TWTs are key devices for high-frequency and high-power amplifiers used in high-resolution imaging applications. This paper presents the design, simulation, and fabrication of W-band pulsed TWTs. For higher power and broader bandwidth, TWTs have been developed using all-metal folded waveguide (FWG) slow-wave structures, diamond-disc windows, and horseshoe-shaped carbonized alumina attenuators. The test results show that W-band FWG pulsed TWTs can reach over 100 W output power with 6.7 GHz bandwidth and over 33 dB saturated gain at 20% duty cycle, while the maximum output power exceeds 200 W. [ABSTRACT FROM AUTHOR]

Abstract: A 75-kW methanol reforming fuel cell system, which consists of a fuel cell system and a methanol auto-thermal reforming fuel processor has been developed at Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS). The core of the fuel cell system is a group of CO tolerant PEMFC stacks with a double layer composite structured anode. The fuel cell stacks show good CO tolerance even though 140ppm CO was present in the reformate stream during transients. The auto-thermal reforming (ATR) fuel cell processor could adiabatically produce a suitable reformate without external energy consumption. The output of hydrogen-rich reformate was approximately 120Nm3 h−1 with a H2 content near 53% and the CO concentrations generally were under 30ppm. The fuel cell system was integrated with the methanol reforming fuel processor and the peak power output of the fuel cell system exceeded 75kW in testing. The hydrogen utilization approached 70% in the fuel cell system. [Copyright &y& Elsevier]

Fabrication of mechanically robust and catalyst-free vitrimers is of great importance, but often challenging. Herein, a facile strategy to achieve this goal by incorporation of intramolecular hydrogen bonds into the dynamic covalent network is demonstrated. Specifically, glycidyl methacrylate (GMA) is reacted with bio-renewable malic acid (MA) to generate a UV-curable resin containing ester linkages. On account of the proximity between the α -carbonyl and β -hydroxyl groups in MA, six-membered-ring intramolecular hydrogen bonds (O-H⋯O=C) are formed in the cross-linked network. This formation of intramolecular hydrogen bonds endows the network with enhanced and outstanding mechanical properties, showing tensile strength and Young's modulus of 117.7 MPa and 3.66 GPa, respectively. Meanwhile, the network is able to efficiently alter its topology without external catalyst through transesterifications reactions at high temperatures. We attributed this phenomenon to the presence of intramolecular hydrogen bonds which make the α -carbonyl carbon more positive and be more reactive towards nucleophilic attack, and thus facilitate the transesterification reaction. This work suggests a promising route to achieve catalyst-free thermosets with superior mechanical performances, good self-healing ability and reprocessability. Image 1 • Fabricating mechanically robust and catalyst-free vitrimer by incorporating intramolecular H-bonds. • The vitrimer shows tensile strength of 117.7 MPa and Young's modulus of 3.6 GPa. • Intramolecular H-bonds showed an accelerated effect on transesterification. • A UV-curable monomer is synthesized to achieve the vitrimer material. [ABSTRACT FROM AUTHOR]