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Due to the limited self-repair ability of the annulus fibrosus (AF), current tissue engineering strategies tend to use structurally biomimetic scaffolds for AF defect repair. However, the poor integration between implanted scaffolds and tissue severely affects their therapeutic effects. To solve this issue, we prepared a multifunctional scaffold containing loaded lysyl oxidase (LOX) plasmid DNA exosomes and manganese dioxide nanoparticles (MnO2NPs). LOX facilitates extracellular matrix (ECM) cross-linking, while MnO2NPs inhibit excessive reactive oxygen species (ROS)-induced ECM degradation at the injury site, enhancing the crosslinking effect of LOX. Our results revealed that this multifunctional scaffold significantly facilitated the integration between the scaffold and AF tissue. Cells were able to migrate into the scaffold, indicating that the scaffold was not encapsulated as a foreign body by fibrous tissue. The functional scaffold was closely integrated with the tissue, effectively enhancing the mechanical properties, and preventing vascular invasion, which emphasized the importance of scaffold-tissue integration in AF repair.

Iron sulfide nanomaterials represented by FeS2and Fe3S4nanozymes have attracted increasing attention due to their biocompatibility and peroxidase-like (POD-like) catalytic activity in disease diagnosis and treatments. However, the mechanism responsible for their POD-like activities remains unclear. Herein, taking the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) by H2O2on FeS2(100) and Fe3S4(001) surfaces, the catalytic mechanism was investigated in detail using density functional theory (DFT) calculations and experimental characterizations. Our experimental results showed that the catalytic activity of FeS2nanozymes was significantly higher than that of Fe3S4nanozymes. Our DFT calculations indicated that the surface iron ions of iron sulfide nanozymes could effectively catalyze the production of HO• radicals via the interactions between Fe 3d electrons and the frontier orbitals of H2O2in the range of −10 to 5 eV. However, FeS2nanozymes exhibited higher POD-like activity due to the surface Fe(II) binding to H2O2, forming inner-orbital complexes, which results in a larger binding energy and a smaller energy barrier for the base-like decomposition of H2O2. In contrast, the surface iron ions of Fe3S4nanozymes bind to H2O2, forming outer-orbital complexes, which results in a smaller binding energy and a larger energy barrier for the base-like decomposition of H2O2. The charge transfer analysis showed that FeS2nanozymes transferred 0.12 e and Fe3S4nanozymes transferred 0.05 e from their surface iron ions to H2O2, respectively. The simulations were consistent with the experimental observations that the FeS2nanozymes had a greater affinity for H2O2compared to that of Fe3S4nanozymes. This work provides a theoretical foundation for the rational design and accurate preparation of iron sulfide functional nanozymes.

Pressure-retarded membrane distillation (PRMD) can convert low-grade heat to useful work by harvesting the pressure energy of the condensation liquid on the cold side. In this study, a new type of PRMD system for combined freshwater and power production was proposed. For this configuration, the thermal energy of the phase change is transported to the interface mainly by conduction rather than convection, which significantly reduces the pump power loss of the liquid flow. In addition, it also utilizes a multistage structure to regenerate heat with low pump power loss. The experimental results showed that, for a module with a heating area of 1.0 m2, this system can produce 188 L of freshwater and 27.8 kJ of power each day when operating between 80°C and 40°C. The water and power densities of the PRMD configuration would be affected by saline ions in the feed liquid, air resistance in the evaporation chamber, membrane wetting, and membrane compaction. The experimental and molecular dynamics simulation results indicated that a higher temperature difference or working temperature will significantly improve the desalination and power generation rates because of the increased mass transfer driving force of the vapor gradient. This study proved that it is possible for a PRMD system to simultaneously obtain net power and freshwater using low-grade heat as the only energy input. Nevertheless, the liquid supply, working pressure, and membrane properties should be improved to achieve better performance.

The dynamic extracellular matrix (ECM) constantly affects the behaviors of cells. To mimic the dynamics of ECM with controllable stiffness and energy dissipation, this study proposes a strategy in which a small molecule, 3,4-dihydroxybenzaldehyde (DB), was used as fast “dynamic bridges'’ to construct viscoelastic gelatin methacryloyl (GelMA)-based hydrogels. The storage modulus and loss modulus of hydrogels were independently adjusted by the covalent crosslinking density and by the number of dynamic bonds. The hydrogels exhibited self-healing property, injectability, excellent adhesion and mechanical properties. Moreover, the in vitroresults revealed that the viscous dissipation of hydrogels favored the spreading, proliferation, osteogenesis and chondrogenesis of bone marrow mesenchymal stem cells (BMSCs), but suppressed their adipogenesis. RNA-sequencing and immunofluorescence suggested that the viscous dissipation of hydrogels activated Yes-associated protein (YAP) by stabilizing integrin β1, and further promoted nuclear translocation of smad2/3 and β-catenin to enhance chondrogenesis and osteogenesis. As a result, the viscoelastic GelMA hydrogels with highest loss modulus showed best effect in cartilage and subchondral bone repair. Taken together, findings from this study reveal an effective strategy to fabricate viscoelastic hydrogels for modulating the interactions between cells and dynamic ECM to promote tissue regeneration.

Atherosclerosis is a primary contributor to cardiovascular disease. Current studies have highlighted the association between the immune system, particularly immune cells, and atherosclerosis, although treatment options and clinical trials remain scarce. Immunotherapy for cardiovascular disease is still in its infancy. Bruton's tyrosine kinase (BTK), widely expressed in various immune cells, represents a promising therapeutic target for atherosclerosis by modulating the anti‐inflammatory function of immune cells. This study introduces a polydopamine‐based nanocarrier system to deliver the BTK inhibitor, ibrutinib, to atherosclerotic plaques with an active targeting property via an anti‐CD47 antibody. Leveraging polydopamine's pH‐sensitive reversible disassembly, the system offers responsive, controlled release within the pathologic microenvironment. This allows precise and efficient ibrutinib delivery, concurrently inhibiting the activation of the NF‐κB pathway in B cells and the NLRP3 inflammasome in macrophages within the plaques. This treatment also modulates both the immune cell microenvironment and inflammatory conditions in atherosclerotic lesions, thereby conveying promising therapeutic effects for atherosclerosis in vivo. This strategy also provides a novel option for atherosclerosis treatment. A nano‐drug delivery system is developed with the properties of active targeting to atherosclerotic plaques and pH‐controlled drug release. It simultaneously inhibits the activation of NF‐κB pathway in B cells and NLRP3 inflammasome in macrophages, leading reduced inflammation and depleted B cells. This strategy of anti‐inflammation by regulating immune cells provides a new option for atherosclerosis treatment.

Nanoprodrugs with responsive release properties integrate the advantages of stimuli-responsive prodrugs and nanotechnology. They would provide ultimate opportunity in fighting atherosclerosis. In this study, we synthesized a redox-responsive nanoprodrug of simvastatin (TPTS) by conjugating α-tocopherol polyethylene glycol derivative to the pharmacophore of simvastatin with a thioketal linker. TPTS formed nanoparticles and released parent simvastatin in the presence of hydrogen peroxide. Moreover, by taking advantage of the self-assembly behavior of TPTS, we developed a fibronectin-targeted delivery system (TPTS/C/T) to codelivery simvastatin prodrug and ticagrelor. In vitro and in vivo experiments indicated that TPTS and TPTS/C/T had good stability, which could reduce off-target leakage of drugs. They greatly inhibited the M1-type polarization of macrophages; reduced intracellular reactive oxygen species level and inflammatory cytokine; and TNF-α, MCP-1, and IL-1β were secreted by macrophage cells, thus providing enhanced anti-inflammatory and antioxidant effects compared with free simvastatin. TPTS/C/T realized targeted drug release to plaques and synergistic therapeutic effects of simvastatin and ticagrelor on atherosclerosis treatment in an ApoE–/– mouse model, resulting in excellent atherosclerosis therapeutic efficacy and a promising biosafety profile. Therefore, this study provides a new method for manufacturing statin nanodrugs and a new design idea for related responsive drug release nanosystems for atherosclerosis.

Passive microwave radiometers onboard satellites rely on the received upwelling radiation to retrieve precipitation, which is a mixed signal from the surface, atmosphere and precipitation hydrometeors. Liquid precipitation droplets increase the upwelling radiation from the surface at lower frequencies, while ice particles cause a decrease in upwelling radiation at higher frequencies. The task of the retrieval algorithm is to identify the precipitation phase and to isolate the signal of precipitation from that of the surface. This study develops a machine learning method to retrieve rainfall and snowfall rates based on observations from the Microwave Hydrometer Sounder and Microwave Temperature Sounder onboard FY‐3E. Self‐organized mapping (SOM) is selected to classify the precipitation and underlying surface types, and an artificial neural network (ANN) is subsequently used to relate the brightness temperature to the precipitation rate for the clusters derived from the SOM. The half‐hour product of the Integrated Multi‐Satellite Retrieval for Global Precipitation Measurement (IMERG) is used to train the ANN. To address the issue that number of heavy precipitation samples are not enough for training, the simulation of radiative transfer for TOVS is used as a supplement to heavy rain samples. The SOM‐ANN algorithm outperforms the IMERG and Goddard profiling algorithm (GPROF) retrieval products in both rainfall and snowfall retrieval. Compared with the hourly observations at ∼4,400 stations during a 2‐year period, the root mean square errors of SOM‐ANN proposed here are 1.06 and 0.34 mm/hr for the rainfall and snowfall rates, which are better than those of IMERG (1.23 and 0.42 mm/hr) and GPROF (1.22 and 0.44 mm/hr). FY‐3E is the first dawn‐dusk orbit meteorological satellite for civil use, and the development of a retrieval algorithm supplements the lack of passive microwave observations in current global precipitation constellation during this period. The Microwave Hydrometer/Temperature Sounder (MWHS/MWTS) onboard FY‐3E can capture radiation information about water vapor, raindrops, and ice crystals, which can be used to retrieve rainfall/snowfall. In particular, the 166 and 183 GHz channels are proved to have advantages in snowfall retrieval. Self‐organized mapping (SOM) is selected to classify the precipitation and underlying surface types, and an artificial neural network (ANN) is subsequently used to relate the brightness temperature to the precipitation rate for the clusters derived from the SOM. The evaluation against gauge observations at ∼4,400 stations over the north hemisphere land during a two year period indicates that the SOM‐ANN method improves the accuracy of rainfall/snowfall retrieval. A machine learning method is proposed to retrieve rainfall and snowfall rates from passive microwave observations from the FY‐3E satelliteThe addition of radiative transfer model enhances the retrieval performance in precipitation intensity distributionThe method better handles the impacts of the underlying surface and precipitation phases, improving the accuracy of the retrieval A machine learning method is proposed to retrieve rainfall and snowfall rates from passive microwave observations from the FY‐3E satellite The addition of radiative transfer model enhances the retrieval performance in precipitation intensity distribution The method better handles the impacts of the underlying surface and precipitation phases, improving the accuracy of the retrieval

Thermo-osmotic energy conversion (TOEC) technology, developed from membrane distillation, is an emerging method that has the potential of obtaining electricity efficiently from a low-grade heat source but faces the difficult problem of pump power loss. In this study, we build a novel TOEC system with a multistage architecture that can work without pump assistance. The experiment system, made of cheap commercial materials, can obtain a power density of 1.39 ± 0.25 W/m2, with a heating temperature of 80 °C, and its efficiency increased linearly with the total stage number. A theory calculation shows that a 30-stage system with a specific membrane and a working pressure of 5.0 MPa can obtain an efficiency of 2.72% with a power density of 14.0 W/m2. By a molecular dynamics simulation, it is shown that a high-performance membrane has the potential to work at 40 MPa. This study proves that TOEC technology is a practical and competitive approach to covert low-grade thermal energy into power efficiently.

High oxygen content in lignite increases hydrogen consumption during hydroliquefaction, and simultaneously the produced water decreases hydrogen partial pressure, which negatively affects lignite liquefaction behaviors. Therefore, the liquefaction performances and oxygen-removal behaviors of Xilinhaote (XL) lignite during liquefaction at different temperatures in the presence of Na2CO3(NC) and FeOOH (FO) were investigated. Results showed that the oxygen contents of liquefaction residues (LRs) obtained at 330–380 °C were 9.37–13.84% without catalyst and decreased to 7.90–13.02% and 6.38–11.73% with the addition of FO and NC, respectively. The addition of NC could promote the polarized breakdown of aromatic Caryl–Calkylether bonds via ionic pathways in the presence of water, which facilitated the depolymerization of lignite macromolecular structures, resulting in significant increase in coal conversions at 330–380 °C. To enhance liquefaction performance, an optimized two-stage catalytic liquefaction process for lignite with high oxygen content was proposed, which integrated the deoxygenation treatment of lignite over Na2CO3and the hydrogenation of Na2CO3-treated lignite over iron catalyst. In the two-stage catalytic liquefaction processes, coal conversions and oil yields significantly increased to 90.66–92.73% and 52.73–57.56%, respectively, compared to 84.61% and 43.52% in single-stage liquefaction of XL over FO at 450 °C. Furthermore, in the two-stage catalytic liquefaction process, the treatment of XL over NC in stage I presented higher coal conversion (92.73%) and oil yield (57.56%) than those over FO in stage I (90.66% and 52.73%). Surprisingly, H2consumption of the former (2.17%) was lower than that of the latter (2.91%).

•LHPs are made of aluminum alloys, and the evaporator structure has been improved.•Non-toxic and environmentally-friendly R1234ze(E) is adopted as the working fluid.•LHPs were experimentally studied and operated under different working conditions.•The largest heat load of the liquid-condenser LHP is 270 W (16.9 W/cm2).•The total thermal resistance of LHPs is low, with a minimum value of 0.115 °C/W.

Urbanization is an important factor that may influence the formation and development of clouds and precipitation. In this study, we focus on studying the influence of urbanization on mesoscale convective systems (MCS) over the Yangtze River Delta region in China under different synoptic conditions using a combination of radiosonde, meteorological station, and satellite observations. It demonstrates that synoptic forcing can be used to distinguish the effect of land cover and land use on MCS. When the synoptic‐scale forcing is weak, the urban heat island (UHI) is the main factor affecting the vertical development of clouds. The UHI decreases atmospheric stability and enhances horizontal convergence, invigorating clouds over and downwind of cities. On the other hand, when strong synoptic‐scale forcing is present, buildings in cities cause clouds to bifurcate upwind of cities, moving around them, primarily through their dynamic effects. The heights of cloud tops in central and downwind parts of cities thus drop. Using the Weather Research and Forecasting model simulations of different atmospheric forcings also demonstrate similar patterns around major urban areas. The joint analyses of observations and model simulations provide new insights into the net effects of urbanization on cloud systems. How the mesoscale convective system (MCS) is affected by urban underlying surface remains largely unknown. Here, we characterize the temporal and spatial variation of MCS in the Yangtze River Delta region by using high‐resolution cloud top temperature observations from geostationary satellite. To better isolate the effect of synoptic‐scale meteorology, the MCS evolution is explicitly investigated with respect to different synoptic‐scale forcing. In the case of strong synoptic forcing, the development of MCS tends to be weakened over and downwind of the urban areas due to the urban‐buildings‐barrier effect. By comparison, under the weak synoptic forcing, urban heat island effect leads to stronger sensible heat flux, which drives the coupling of planetary boundary layer and cloud, and promotes the development of MCS over and downwind of the urban areas. Further analyses based on Weather Research and Forecasting model simulation verify the observational phenomena. The findings obtained here will help advance our understanding of the net effects of urbanization on cloud systems, which provides new insights for the mechanism of urbanization‐induced convective initiation. Synoptic forcing is a key factor dictating the effect of land cover and land use changes on mesoscale convective systems (MCS)Weak (strong) large‐scale forcing invigorates (weakens) the vertical development of MCS over and downwind of citiesThe urban heat island effect is more dominant under weak synoptic forcing, whereas the urban‐building‐barrier effect is more prominent under strong forcing Synoptic forcing is a key factor dictating the effect of land cover and land use changes on mesoscale convective systems (MCS) Weak (strong) large‐scale forcing invigorates (weakens) the vertical development of MCS over and downwind of cities The urban heat island effect is more dominant under weak synoptic forcing, whereas the urban‐building‐barrier effect is more prominent under strong forcing

•A pump-assisted loop heat pipe with two parallel evaporators was fabricated.•Both biporous wick and impeller micropump were used to provide the driving force.•The maximum heat flux was 27.5 W/cm2and evaporator 2 performed better.•Higher pump power and lower heat sink temperature enhanced thermal performance.•The minimum thermal resistances for the two evaporators were 0.217 and 0.197 °C/W.

With the increasing popularity of cloud computing applications, the threat of malware attack against cloud environments is getting worse. To defend against malware attacks in the cloud, some virtualization‐based approaches are proposed. However, the existing methods suffer from limitations in terms of detection accuracy, deployment effort, and performance cost. To address these issues, we propose MDCD, a novel dynamic malware detection solution for cloud environments. This method first utilizes a lightweight agent to collect the run‐time utilization information from the target virtual machine (VM). Then, it leverages the memory forensics analysis technique to extract the memory object information from the target VM's memory. To fully make use of the run‐time utilization and memory object information for malware detection, we propose a multi‐CNN model, which combines multiple convolutional neural networks (CNNs) efficiently. The evaluation shows that our approach can achieve an average detection accuracy, precision, recall, and F1 Score of 98.89%, 97.01%, 98.17%, and 97.89% respectively. Compared with the existing solutions, our method can detect multiple malicious processes effectively with little deployment effort. We present MDCD, a malware detection system for virtualization environments. By utilizing the run‐time utilization and memory object information of the target VM, we can effectively detect the malicious programs in the target VM.

There is an urgent clinical need for the treatment of annulus fibrosus (AF) impairment caused by intervertebral disc (IVD) degeneration or surgical injury. Although repairing injured AF through tissue engineering is promising, the approach is limited by the complicated angle‐ply microstructure, inflammatory microenvironment, poor self‐repairing ability of AF cells and deficient matrix production. In this study, electrospinning technology is used to construct aligned core–shell nanofibrous scaffolds loaded with transforming growth factor‐β3 (TGFβ3) and ibuprofen (IBU), respectively. The results confirm that the rapid IBU release improves the inflammatory microenvironment, while sustained TGFβ3 release enhances nascent extracellular matrix (ECM) formation. Biomaterials for clinical applications must repair local AF defects during herniectomy and enable AF regeneration during disc replacement, so a box defect model and total IVD replacement model in rat tail are constructed. The dual‐drug delivering electrospun scaffolds are assembled into angle‐ply structure to form a highly biomimetic AF that is implanted into the box defect or used to replace the disc. In two animal models, it is found that biomimetic scaffolds with good anti‐inflammatory ability enhance ECM formation and maintain the mechanical properties of IVD. Findings from this study demonstrate that the multifunctional nanofibrous scaffolds provide inspirations for IVD repair. A novel aligned core–shell nanofibrous scaffold with angle‐ply microstructure and co‐delivery capacity is developed and its ability to repair and regenerate annulus fibrosus (AF) is tested. Burst release of ibuprofen can regulate the inflammatory microenvironment, and sustained release of transforming growth factor‐β3 can promote the secretion of extracellular matrix. It can not only repair the damaged AF, but also realize regeneration of intervertebral discs.

Biomimetic Structures Annulus fibrosus (AF) repair is critical for treating disc herniation. In article 2200895, Fengxuan Han, Bin Li, and co‐workers fabricate aligned core–shell nanofibrous scaffolds mimicking AF microstructure and realize temporal release of drugs for AF repair. Fast release of ibuprofen‐ameliorated inflammation and sustained release of TGFβ3 promote cell proliferation and ECM secretion.