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Tau protein is a microtubule-associated protein that is widely distributed in the central nervous system and maintains and regulates neuronal morphology and function. Tau protein aggregates abnormally and forms neurofibrillary tangles in neurodegenerative diseases, disrupting the structure and function of neurons and leading to neuronal death, which triggers the initiation and progression of neurological disorders. The aggregation of tau protein in neurodegenerative diseases is associated with post-translational modifications, which may affect the hydrophilicity, spatial conformation, and stability of tau protein, promoting tau protein aggregation and the formation of neurofibrillary tangles. Therefore, studying the role of tau protein in neurodegenerative diseases and the mechanism of aberrant aggregation is important for understanding the mechanism of neurodegenerative diseases and finding therapeutic approaches. This review describes the possible mechanisms by which tau protein promotes neurodegenerative diseases, the post-translational modifications of tau protein and associated influencing factors, and the current status of drug discovery and development related to tau protein, which may contribute to the development of new therapeutic approaches to alleviate or treat neurodegenerative diseases.

The collision between India and Eurasia mobilizes multiple processes of continental tectonics. However, how deformation develops within the lithosphere across the Tibetan Plateau is still poorly known and a synoptic view is missing. Here, we exploit an extensive geodetic observatory to resolve the kinematics of this diffuse plate boundary and the arrangement of various mechanisms down to upper-mantle depths. The three-dimensional velocity field is compatible with continental underthrusting below the central Himalayas and with delamination rollback below the western syntaxis. The rise of the Tibetan Plateau occurs by shortening in the Indian and Asian crusts at its southern and northwestern margins. The subsidence of Central Tibet is associated with lateral extrusion and attendant lithospheric thinning aided by the downwelling current from the opposite-facing Indian and Asian collisions. The current kinematics of the Indian-Eurasian collision may reflect the differential evolution of the inner and outer Tibetan Plateau during the late Cenozoic.

Metamaterials have demonstrated great potential for controlling wave propagation since they are flexibly adjustable. A new one-dimensional metamaterial model with both a negative effective moment of inertia and negative effective stiffness is proposed. A negative effective moment of inertia and negative effective stiffness can be achieved by adjusting the structural parameters in certain frequency ranges. Bandgaps in the low-frequency range with exponential wave attenuation can be generated in the metamaterial. A flat band is obtained that couples two Bragg bandgaps to achieve a wide bandgap in the low-frequency range, where the effective moment of inertia and effective stiffness are both infinite. A zero-frequency bandgap can be achieved by adjusting the structural parameters. Quick attenuation of wave is observed in the zero-frequency ranges with single-negative parameters. Furthermore, an ultrawide-zero-frequency bandgap is obtained by optimizing the structural parameters of the system. In addition, it is easy to switch between the Bragg and locally resonant bandgaps. This new metamaterial can be applied to ultralow-frequency-vibration isolation.

Supercapacitor is highly demanded in emerging portable electronics, however, which faces frequent charging and inevitable rapid self-discharging of huge inconvenient. Here, we present a flexible moisture-powered supercapacitor (mp-SC) that capable of spontaneously moisture-enabled self-charging and persistently voltage stabilizing. Based on the synergy effect of moisture-induced ions diffusion of inner polyelectrolyte-based moist-electric generator and charges storage ability of inner graphene electrochemical capacitor, this mp-SC demonstrates the self-charged high areal capacitance of 138.3 mF cm −2 and ~96.6% voltage maintenance for 120 h. In addition, a large-scale flexible device of 72 mp-SC units connected in series achieves a self-charged 60 V voltage in air, efficiently powering various commercial electronics in practical applications. This work will provide insight into the design self-powered and ultra-long term stable supercapacitors and other energy storage devices. The recharging and rapid self-discharge of supercapacitors imposes constraints on their application. In response, the authors have developed a moisture-powered supercapacitor capable of self-charging and voltage stabilizing by absorbing water in air.

Auxetic materials exhibiting a negative Poisson’s ratio are of great research interest due to their unusual mechanical responses and a wide range of potential deployment. Efforts have been devoted to exploring novel 2D and 3D auxetic structures through rational design, optimization, and taking inspiration from nature. Here we report a 3D architected lattice system showing a negative Poisson’s ratio over a wide range of applied uniaxial stretch. 3D printing, experimental tests, numerical simulation, and analytical modeling are implemented to quantify the evolution of the Poisson’s ratio and reveal the underlying mechanisms responsible for this unusual behavior. We further show that the auxetic behavior can be controlled by tailoring the geometric features of the ligaments. The findings reported here provide a new routine to design architected metamaterial systems exhibiting unusual properties and having a wide range of potential applications.

Hot electrons can dramatically improve the efficiency of solar cells and sensitize energetically-demanding photochemical reactions. Efficient hot electron devices have been hindered by sub-picosecond intraband cooling of hot electrons in typical semiconductors via electron-phonon scattering. Semiconductor quantum dots were predicted to exhibit a “phonon bottleneck” for hot electron relaxation as their quantum-confined electrons would couple very inefficiently to phonons. However, typical cadmium selenide dots still exhibit sub-picosecond hot electron cooling, bypassing the phonon bottleneck possibly via an Auger-like process whereby the excessive energy of the hot electron is transferred to the hole. Here we demonstrate this cooling mechanism can be suppressed in copper-doped cadmium selenide colloidal quantum dots due to femtosecond hole capturing by copper-dopants. As a result, we observe a lifetime of ~8.6 picosecond for 1 P e hot electrons which is more than 30-fold longer than that in same-sized, undoped dots (~0.25 picosecond). Weak electron-phonon scattering that can enable long-lived hot electrons in semiconductors is of interest in hot carrier solar cells. Here, the authors report copper-doped colloidal cadmium-selenide quantum dots with hot electron lifetime extended by more than 30-fold compared to undoped dots.

Complex metal nanoparticles distributed uniformly on supports demonstrate distinctive physicochemical properties and thus attract a wide attention for applications. The commonly used wet chemistry methods display limitations to achieve the nanoparticle structure design and uniform dispersion simultaneously. Solid-phase synthesis serves as an interesting strategy which can achieve the fabrication of complex metal nanoparticles on supports. Herein, the solid-phase synthesis strategy is developed to precisely synthesize uniformly distributed CoFe@FeO x core@shell nanoparticles. Fe atoms are preferentially exsolved from CoFe alloy bulk to the surface and then be carburized into a Fe x C shell under thermal syngas atmosphere, subsequently the formed Fe x C shell is passivated by air, obtaining CoFe@FeO x with a CoFe alloy core and a FeO x shell. This strategy is universal for the synthesis of MFe@FeO x (M = Co, Ni, Mn). The CoFe@FeO x exhibits bifunctional effect on regulating polysulfides as the separator coating layer for Li-S and Na-S batteries. This method could be developed into solid-phase synthetic systems to construct well distributed complex metal nanoparticles. Solid-phase synthesis strategy is promising for fabricating desired complex metal nanoparticles on supports. Here, the authors synthesize CoFe@FeOx core-shell nanoparticles as the separator coatings via precise solid-phase method which effectively regulates polysulfides for lithium/ sodium-sulfur batteries.

A key process underlying the application of low-dimensional, quantum-confined semiconductors in energy conversion is charge transfer from these materials, which, however, has not been fully understood yet. Extensive studies of charge transfer from colloidal quantum dots reported rates increasing monotonically with driving forces, never displaying an inverted region predicted by the Marcus theory. The inverted region is likely bypassed by an Auger-like process whereby the excessive driving force is used to excite another Coulomb-coupled charge. Herein, instead of measuring charge transfer from excitonic states (coupled electron-hole pairs), we build a unique model system using zero-dimensional quantum dots or two-dimensional nanoplatelets and surface-adsorbed molecules that allows for measuring charge transfer from transiently-populated, single-charge states. The Marcus inverted region is clearly revealed in these systems. Thus, charge transfer from excitonic and single-charge states follows the Auger-assisted and conventional Marcus charge transfer models, respectively. This knowledge should enable rational design of energetics for efficient charge extraction from low-dimensional semiconductor materials as well as suppression of the associated energy-wasting charge recombination. Marcus inverted region for charge transfer from low-dimensional semiconductor materials has been long sought after. Here, the authors reveal this region by directly measuring charge transfer from single-charge states rather than excitonic states.

Hypervirulent Klebsiella pneumoniae (HvKP) is hypermucoviscous organism, carrying genes of rmpA and aerobactin, causing serious community-acquired infection and metastatically spread in young healthy hosts. Neutrophils play an important role during innate immune response against bacterial infection by phagocytosis and neutrophil extracellular traps (NETs). Whether neutrophils can effectively defend against HvKP remains unclear. In this study, we observed that the HvKP was significantly more resistant to neutrophil-mediated phagocytosis and intracellular killing than classic Klebsiella pneumoniae (cKP) isolates. Although both HvKP and cKP induced NETs under scanning electron microscopy and confocal microscopy, more cKP than HvKP were trapped in NETs, and the killing by intracellular and extracellular mechanisms of neutrophils was detected only on cKP. Together, our results demonstrated that HvKP resisted to both intracellular and extracellular killing of neutrophils.

Reinforced concrete (RC) beam–column joints are vulnerable to brittle failure under seismic actions due to their limited deformation capacity, posing a threat to the overall safety of RC frames. To address this issue, this study proposes and evaluates a novel strengthening strategy for RC joints using an engineered cementitious composite (ECC) shell, forming a beam–column joint with an ECC shell (BCJES). The mechanical behavior of the BCJES under cyclic loading was investigated through a refined finite element (FE) model. The FE model, validated against test results, enabled a systematic parametric study to quantify the effects of ECC shell height and thickness, longitudinal reinforcement ratio (at the beam region), and axial compression ratio on seismic performance. Results demonstrate that the proposed ECC shell markedly enhances the seismic capacity of RC joints. Increasing the longitudinal reinforcement ratio from 0.05% to 0.2% improved peak load from 33.87 to 85.58 kN (152%), while increasing shell thickness from 30 to 90 mm enhanced peak load by 11.9%. However, a saturation effect was observed, as further thickening the shell to 150 mm resulted in only a 2.46% gain. Based on the parametric results, this study, for the first time, establishes a quantitative predictive model for the ultimate bearing capacity of BCJES using multiple linear regression (R²= 0.943). Furthermore, a new theoretical shear–capacity model incorporating both main and lateral diagonal bracing mechanisms is developed. Theoretical predictions agree well with FE simulations and experimental results, with maximum deviations of only 7.5% and 7.9%, respectively, confirming the reliability of the proposed approach. These findings highlight the potential of the ECC shell as an effective and practical seismic-strengthening solution for RC joints, offering new insights for performance-based design and retrofit strategies.