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The activation of host’s innate and adaptive immune systems can lead to acute and chronic graft rejection, which seriously impacts graft survival. Thus, it is particularly significant to clarify the immune signals, which are critical to the initiation and maintenance of rejection generated after transplantation. The initiation of response to graft is dependent on sensing of danger and stranger molecules. The ischemia and reperfusion of grafts lead to cell stress or death, followed by releasing a variety of damage-associated molecular patterns (DAMPs), which are recognized by pattern recognition receptors (PRRs) of host immune cells to activate intracellular immune signals and induce sterile inflammation. In addition to DAMPs, the graft exposed to ‘non-self’ antigens (stranger molecules) are recognized by the host immune system, stimulating a more intense immune response and further aggravating the graft damage. The polymorphism of MHC genes between different individuals is the key for host or donor immune cells to identify heterologous ‘non-self’ components in allogeneic and xenogeneic organ transplantation. The recognition of ‘non-self’ antigen by immune cells mediates the activation of immune signals between donor and host, resulting in adaptive memory immunity and innate trained immunity to the graft, which poses a challenge to the long-term survival of the graft. This review focuses on innate and adaptive immune cells receptor recognition of damage-associated molecular patterns, alloantigens and xenoantigens, which is described as danger model and stranger model. In this review, we also discuss the innate trained immunity in organ transplantation.

With urbanization, municipal solid waste (MSW) generation is increasing. Traditional landfill methods face land shortages and environmental pollution. Waste incineration, which reduces waste and recovers resources, has become a key management method. However, nitrogen oxides (NO x ) produced during incineration severely impact the environment, requiring improved control technologies. This study optimized three denitrification technologies—air staging, flue gas recirculation (FGR), and selective non-catalytic reduction (SNCR)—using numerical simulations. The research provides support for improving waste incinerator efficiency and stability while reducing NOx emissions, aiding the sustainable development of waste incineration technology. By optimizing the primary and secondary air distribution ratios, the initial NOx generation was reduced by 8.39%. When 20% of the recirculated flue gas was introduced as secondary air, NOx generation was reduced by 23.54%, and boiler efficiency increased to 83.78%. The study examined the impact of different sludge mixing ratios on the temperature and NOx emissions within the context of municipal solid waste (MSW) incineration. Initially, the study aimed to address the environmental concerns of NOx emissions during the incineration process by exploring how the introduction of sludge at various mixing ratios would affect combustion parameters. The results showed that a sludge mixing ratio between 3 and 13% optimized the combustion process with 7% being the most effective in balancing temperature control and NOx emissions. Specifically, the best value of the sludge mixing ratio refers to achieving an optimal reduction in NOx emissions while maintaining stable incinerator operation. The chemical compositions of the sludge included key elements such as carbon (C), hydrogen (H), nitrogen (N), sulfur (S), and oxygen (O), with approximate proportions of C: 31.2%, H: 4.7%, N: 2.5%, S: 0.6%, and O: 31.8%.

Developing devices with a wide-temperature range persistent photoconductivity (PPC) and ultra-low power consumption remains a significant challenge for optical synaptic devices used in neuromorphic computing. By harnessing the PPC properties in materials, it can achieve optical storage and neuromorphic computing, surpassing the von Neuman architecture-based systems. However, previous research implemented PPC required additional gate voltages and low temperatures, which need additional energy consumption and PPC cannot be achieved across a wide temperature range. Here, we fabricated a simple heterojunctions using zinc(II)-meso-tetraphenyl porphyrin (ZnTPP) and single-walled carbon nanotubes (SWCNTs). By leveraging the strong binding energy at the heterojunction interface and the unique band structure, the heterojunction achieved PPC over an exceptionally wide temperature range (77 K-400 K). Remarkably, it demonstrated nonvolatile storage for up to 2×10 4  s, without additional gate voltage. The minimum energy consumption for each synaptic event is as low as 6.5 aJ. Furthermore, we successfully demonstrate the feasibility to manufacture a flexible wafer-scale array utilizing this heterojunction. We applied it to autonomous driving under extreme temperatures and achieved as a high impressive accuracy rate as 94.5%. This tunable and stable wide-temperature PPC capability holds promise for ultra-low-power neuromorphic computing. Devices with a wide-temperature range persistent photoconductivity (PPC) and low power consumption is a challenge for optical synaptic devices in neuromorphic computing. Here, the authors develop a carbon nanotube/porphyrin heterojunction on a flexible array, achieving PPC between 77 K to 400 K.

Surface-enhanced Raman spectroscopy (SERS) represents a very powerful tool for the identification of molecular species, but unfortunately it has been essentially restricted to noble metal supports (Au, Ag and Cu). While the application of semiconductor materials as SERS substrate would enormously widen the range of uses for this technique, the detection sensitivity has been much inferior and the achievable SERS enhancement was rather limited, thereby greatly limiting the practical applications. Here we report the employment of non-stoichiometric tungsten oxide nanostructure, sea urchin-like W 18 O 49 nanowire, as the substrate material, to magnify the substrate–analyte molecule interaction, leading to significant magnifications in Raman spectroscopic signature. The enrichment of surface oxygen vacancy could bring additional enhancements. The detection limit concentration was as low as 10 −7  M and the maximum enhancement factor was 3.4 × 10 5 , in the rank of the highest sensitivity, to our best knowledge, among semiconducting materials, even comparable to noble metals without ‘hot spots’. Surface-enhanced Raman spectroscopy is widely used for rapid and sensitive molecular detection in chemistry and biology, but typically relies on noble metals. Here the authors report a non-stoichiometric semiconducting material with defect-rich surface that displays excellent detection limits and enhancement factors.

In this work, we report the monolithic three-dimensional integration (M3D) of hybrid memory architecture based on resistive random-access memory (RRAM), named M3D-LIME. The chip featured three key functional layers: the first was Si complementary metal-oxide-semiconductor (CMOS) for control logic; the second was computing-in-memory (CIM) layer with HfAlO x -based analog RRAM array to implement neural networks for feature extractions; the third was on-chip buffer and ternary content-addressable memory (TCAM) array for template storing and matching, based on Ta 2 O 5 -based binary RRAM and carbon nanotube field-effect transistor (CNTFET). Extensive structural analysis along with array-level electrical measurements and functional demonstrations on the CIM and TCAM arrays was performed. The M3D-LIME chip was further used to implement one-shot learning, where ~96% accuracy was achieved on the Omniglot dataset while exhibiting 18.3× higher energy efficiency than graphics processing unit (GPU). This work demonstrates the tremendous potential of M3D-LIME with RRAM-based hybrid memory architecture for future data-centric applications. Designing efficient 3D artificial neural networks chip remains a challenge. Here, the authors report a M3D-LIME chip with monolithic three-dimensional integration of hybrid memory architecture based on resistive random-access memory, which achieves a high classification accuracy of 96% in one-shot learning task while exhibiting 18.3× higher energy efficiency than GPU.

Horizontal arrays of metallic or semiconducting carbon nanotubes with controlled chirality are grown from specially designed solid carbide catalysts. Controlling the chirality of carbon nanotubes The era of Moore's law, which predicts a doubling in the number of transistors per microprocessor chip every two years, seems to be coming to an end. Researchers are therefore developing alternative materials to use in nanoelectronic devices. Arrays of horizontal nanotubes are particularly appealing because this architecture optimizes current output. Now Jin Zhang and colleagues report the synthesis of two different horizontal carbon nanotube arrays with controlled chirality, one metallic and one semiconducting. The authors achieve this by using catalyst arrays that are designed to select for nanotubes with a specific diameter and crystal symmetry. The authors target nanotubes with the chiral structure (2 m , m ), which is fast growing and can be further enriched by optimizing the growth conditions. These findings are a further step towards a new generation of high-performance electronic devices and integrated circuits based on carbon nanotechnology. The semiconductor industry is increasingly of the view that Moore’s law—which predicts the biennial doubling of the number of transistors per microprocessor chip—is nearing its end 1 . Consequently, the pursuit of alternative semiconducting materials for nanoelectronic devices, including single-walled carbon nanotubes (SWNTs), continues 2 , 3 , 4 . Arrays of horizontal nanotubes are particularly appealing for technological applications because they optimize current output. However, the direct growth of horizontal SWNT arrays with controlled chirality, that would enable the arrays to be adapted for a wider range of applications and ensure the uniformity of the fabricated devices, has not yet been achieved. Here we show that horizontal SWNT arrays with predicted chirality can be grown from the surfaces of solid carbide catalysts by controlling the symmetries of the active catalyst surface. We obtained horizontally aligned metallic SWNT arrays with an average density of more than 20 tubes per micrometre in which 90 per cent of the tubes had chiral indices of (12, 6), and semiconducting SWNT arrays with an average density of more than 10 tubes per micrometre in which 80 per cent of the nanotubes had chiral indices of (8, 4). The nanotubes were grown using uniform size Mo 2 C and WC solid catalysts. Thermodynamically, the SWNT was selectively nucleated by matching its structural symmetry and diameter with those of the catalyst. We grew nanotubes with chiral indices of (2 m , m ) (where m is a positive integer), the yield of which could be increased by raising the concentration of carbon to maximize the kinetic growth rate in the chemical vapour deposition process. Compared to previously reported methods, such as cloning 5 , 6 , seeding 7 , 8 and specific-structure-matching growth 9 , 10 , 11 , our strategy of controlling the thermodynamics and kinetics offers more degrees of freedom, enabling the chirality of as-grown SWNTs in an array to be tuned, and can also be used to predict the growth conditions required to achieve the desired chiralities.

Nano- and microplastics (NMPs) have become a serious global environmental threat that causes damage to mammalian organs. In this work, we investigated the potential molecular mechanism underlying the development of liver fibrosis induced by long-term exposure to three different sized polystyrene (PS)-NMPs (80 nm, 0.5 µm and 5 µm) in mice. Liver fibrosis levels were evaluated in mice after chronic exposure to PS-NMPs. Liver inflammation was mainly increased in chronic exposure to 80 nm and 0.5 µm PS-NMPs. Liver lipid deposition was significantly enhanced after PS-NMPs exposure. However, oxidative stress was not changed under PS-NMPs exposure. GO enrichment and KEGG pathway analyses revealed that the DEGs and shared DEGs were mainly enriched in the metabolism of lipids. The mRNA expression levels of genes related to fatty acid oxidation, synthesis and transport were dramatically induced by PS-NMPs exposure. Four hub genes, Acot3 , Abcc3 , Nr1i3 and Fmo2 , were identified by CytoHubba analysis of shared DEGs. The mRNA expression levels of three hub genes, Acot3 , Abcc3 and Nr1i3 , were significantly augmented under chronic PS-NMPs exposure. Our results suggest that Acot3 , Abcc3 and Nr1i3 are potential molecules involved in the development of liver fibrosis under chronic exposure to PS-NMPs.

To investigate the influence of the fractured rock-concrete interface on the mechanical response of the rock mass and engineering, the mechanical properties and energy evolution of granite-concrete composite specimens with 16 different fracture inclinations were examined through uniaxial compression particle flow simulation. The results show that when the relative area is constant, the larger the fracture dip angle is, the compressive strength of the composite body presents a similar “peak” type change; the dip angle appears to have the maximum value at 60 o and 90 o and the minimum value at 0 o and 30 o , while the peak elastic modulus presents a “waterfall” type change, and the maximum value appears at 90 o . The crack types were classified as shear cracks, tensile cracks, secondary shear cracks, secondary tensile cracks, shear-dominated mixed cracks, and tension-dominated mixed cracks. From the crack distribution, it was found that the root cause of crack initiation and propagation was affected by the crack inclination angle. The damage degree increased gradually with the increase of crack inclination angle. When the crack inclination angle was constant, the deterioration degree of the specimen weakened with the increase of relative area s. The elastic energy consumption ratio increases with the shaft deformation, first rapidly and steeply decreasing to the steady inflection point, then slowly increasing to the rapid and steep increase, showing a “fishhook” shape. When the strength failure occurs, the growth speed increases suddenly, and the elastic energy consumption ratio increases suddenly after the K peak. This phenomenon can be used as the basis for the occurrence of strength failure and can be used as a qualitative judgment of strength failure.

HighlightsMicrowave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance.Outstanding reflection loss value (−62.7 dB), broadband wave absorption (6.4 dB with only 2.1 mm thickness) in combination with flexible adjustment abilities were acquired, which is superior to other relative graded distribution structures.This strategy initiates a new method for designing and controlling wave absorber with excellent impedance matching property in practical applications.In the present paper, a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance. The inorganic–organic competitive coating strategy was employed, which can effectively adjust the thermodynamic and kinetic reactions of iron ions during the solvothermal process. As a result, Fe nanoparticles can be gradually decreased from the inner side to the surface across the hollow carbon shell. The results reveal that it offers an outstanding reflection loss value in combination with broadband wave absorption and flexible adjustment ability, which is superior to other relative graded distribution structures and satisfied with the requirements of lightweight equipment. In addition, this work elucidates the intrinsic microwave regulation mechanism of the multiscale hybrid electromagnetic wave absorber. The excellent impedance matching and moderate dielectric parameters are exhibited to be the dominative factors for the promotion of microwave absorption performance of the optimized materials. This strategy to prepare gradient-distributed microwave absorbing materials initiates a new way for designing and fabricating wave absorber with excellent impedance matching property in practical applications.

In coal mining environments with complex topographic and geological conditions, the presence of primary cracks in the rock strata of the upper mining airspace is critical to mine safety, especially when roof slabs are broken. Cracked roof slabs not only increase risks during mining but also make mining operations more challenging. Therefore, studying the initial damage state of the roof rock formation is great significance. In this study, the effects of different prefabricated crack sizes and inclination angles on the mechanical properties of the coal-rock composite containing cracks were analyzed through the uniaxial compression experiments and PFC 2D numerical simulations. The results show that the peak strength and elastic modulus of the coal-rock composites fall between those of pure coal and sandstone, while the macroscopic mechanical parameters of crack-containing composites are significantly lower than those of non-crack-containing composites. Coal-rock composites with different crack characteristics exhibited different mechanical properties, with their damage modes were caused by the combined effects of tensile and shear damage. The increase in crack inclination altered the crack extension path, and the final damage of the specimen manifested first in the upper part, then the middle part, and ultimately in the lower part of the coal body, with tension-induced bulk damage being the dominant failure mode. Analysis of the radial cumulative map revealed that cracks primarily extended along 90° and 270° directions, indicating a strong tendency for crack propagation under axial pressure. The damage evolution curves indicate a nonlinear relationship between the damage factor and strain. While increased crack inclination enhances the compressive performance of coal-rock composites, it simultaneously accelerates structural destabilization. These findings offer theoretical insights into the damage mechanisms of coal-rock composites with cracks, serving as valuable references for coal mining safety.