Highlights
The large-sheet holey graphene framework/SiO (LHGF/SiO) composite displays notably high recoverable strain, suggesting considerably improved mechanical flexibility and robustness
The ...LHGF/SiO anode with a mass loading of 44 mg cm
−2
delivers a high areal capacity of 35.4 mAh cm
−2
at current density of 8.8 mA cm
−2
and retains a capacity of 10.6 mAh cm
−2
at 17.6 mA cm
−2
The LHGF/SiO anode with an ultra-high mass loading of 94 mg cm
−2
delivers an extraordinary areal capacity up to 140.8 mAh cm
−2
, about 1–2 order of magnitude higher than those in typical commercial devices
Silicon monoxide (SiO) is an attractive anode material for next-generation lithium-ion batteries for its ultra-high theoretical capacity of 2680 mAh g
−1
. The studies to date have been limited to electrodes with a relatively low mass loading (< 3.5 mg cm
−2
), which has seriously restricted the areal capacity and its potential in practical devices. Maximizing areal capacity with such high-capacity materials is critical for capitalizing their potential in practical technologies. Herein, we report a monolithic three-dimensional (3D) large-sheet holey graphene framework/SiO (LHGF/SiO) composite for high-mass-loading electrode. By specifically using large-sheet holey graphene building blocks, we construct LHGF with super-elasticity and exceptional mechanical robustness, which is essential for accommodating the large volume change of SiO and ensuring the structure integrity even at ultrahigh mass loading. Additionally, the 3D porous graphene network structure in LHGF ensures excellent electron and ion transport. By systematically tailoring microstructure design, we show the LHGF/SiO anode with a mass loading of 44 mg cm
−2
delivers a high areal capacity of 35.4 mAh cm
−2
at a current of 8.8 mA cm
−2
and retains a capacity of 10.6 mAh cm
−2
at 17.6 mA cm
−2
, greatly exceeding those of the state-of-the-art commercial or research devices. Furthermore, we show an LHGF/SiO anode with an ultra-high mass loading of 94 mg cm
−2
delivers an unprecedented areal capacity up to 140.8 mAh cm
−2
. The achievement of such high areal capacities marks a critical step toward realizing the full potential of high-capacity alloy-type electrode materials in practical lithium-ion batteries.
In this work, we consider an online enrichment procedure in the context of the Generalized Multiscale Finite Element Method (GMsFEM) for the two-phase flow model in highly heterogeneous porous media. ...The coefficient of the pressure equation is referred to as the permeability and is the main source of heterogeneity within the model. The elliptic pressure equation is solved using online GMsFEM, which is coupled with a hyperbolic transport equation where local conservation of mass is necessary. To satisfy the conservation property, we aim at constructing conservative fluxes within the space of multiscale basis functions through the use of a postprocessing technique. In order to improve the accuracy of the pressure and velocity solutions in the online GMsFEM, we apply a systematic online enrichment procedure. The increase in pressure accuracy due to the online construction is inherited by the conservative flux fields and the desired saturation solutions from the coupled transport equation. Despite the fact that the coefficient of the pressure equation is dependent on the saturation which may vary in time, we construct an approximation space using the absolute permeability field (
λ
(
S
) = 1) and no further basis updates follow. Numerical results corresponding to three different types of heterogeneous permeability coefficients are exhibited to show the performance of the proposed methodology.
Efficient and accurate numerical methods for elastic wave modeling in complex media have many important applications. However, it is fairly challenging to model elastic wave propagation in strongly ...heterogeneous media with high computational efficiency and high-order accuracy simultaneously. We develop a novel high-order multiscale finite-element method to model elastic wave propagation in strongly heterogeneous media in the time domain. The most important feature of our method is a generalization of standard multiscale finite element method by using high-order multiscale finite-element basis functions to capture the fine-scale heterogeneities on the coarse mesh, in contrast to conventional finite-element basis functions that are merely determined by the order of polynomials. These multiscale basis functions leads to a system matrix with significantly reduced dimension, thus enable us to solve the elastic wave equation on the coarse mesh with high-order accuracy and very low computational time cost. We use 2D and 3D numerical examples to demonstrate the superior efficiency and accuracy of our new modeling method compared with the conventional spectral-element method.
•We develop a higher multiscale finite element method for elastic wave propagation in strongly heterogeneous media.•This new approach is very accurate and efficient due to the higher oder basis functions are used.•The idea of constructing higher oder multiscale basis functions can be extended to other Galerkin formulations.
It is important to develop fast yet accurate numerical methods for seismic wave propagation to characterize complex geological structures and oil and gas reservoirs. However, the computational cost ...of conventional numerical modeling methods, such as finite-difference method and finite-element method, becomes prohibitively expensive when applied to very large models. We propose a Generalized Multiscale Finite-Element Method (GMsFEM) for elastic wave propagation in heterogeneous, anisotropic media, where we construct basis functions from multiple local problems for both the boundaries and interior of a coarse node support or coarse element. The application of multiscale basis functions can capture the fine scale medium property variations, and allows us to greatly reduce the degrees of freedom that are required to implement the modeling compared with conventional finite-element method for wave equation, while restricting the error to low values. We formulate the continuous Galerkin and discontinuous Galerkin formulation of the multiscale method, both of which have pros and cons. Applications of the multiscale method to three heterogeneous models show that our multiscale method can effectively model the elastic wave propagation in anisotropic media with a significant reduction in the degrees of freedom in the modeling system.
An increasing number of studies have found that use of traditional anesthetics may lead to cognitive impairment of the immature brain. Our previous studies verified that cyclin-dependent kinase 5 ...(CDK5) plays a role in sevoflurane-induced cognitive dysfunction. Autophagy was shown to protect against anesthesia-induced nerve injury. Therefore, the current study aimed to ascertain if autophagy participates in anesthesia-induced neurotoxicity. In this study, primary hippocampal neurons were isolated and utilized for experiments in vitro. We also performed in vivo experiments with 6-day-old wild-type mice treated with or without roscovitine (Rosc, a CDK5 inhibitor) or 3-methyladenine (3-Ma, an autophagy inhibitor) after exposure to sevoflurane. We used the Morris water maze to analyze cognitive function. Immunohistochemical staining was used to assess pathologic changes in the hippocampus. The results showed that suppressing CDK5 reversed sevoflurane-induced nerve cell apoptosis both in vivo and in vitro and demonstrated that inhibits CDK5 activation promoted Sirtuin 1 (Sirt1) expression, which functions importantly in induced autophagy activation. Suppression of Sirt1 expression inhibited the protective effect of Rosc on sevoflurane-induced nerve injury by inhibiting autophagy activation. Our in vivo experiments also found that pretreatment with 3-Ma attenuated the protective effect of Rosc on sevoflurane-induced nerve injury and cognitive dysfunction. We conclude that inhibits CDK5 activation restored sevoflurane-induced cognitive dysfunction by promoting Sirt1-mediated autophagy.
Dehydroevodiamine (DHE) is a quinazoline alkaloid isolated from
Evodiae Fructus
(EF,
Wuzhuyu
in Chinese, Rutaceae family), a well-known traditional Chinese medicine (TCM) which is clinically applied ...to treat headache, abdominal pain, menstrual pain, abdominal distension, vomiting, acid regurgitation,
etc.
Modern research demonstrates that DHE is one of the main components of EF. In recent years, DHE has received extensive attention due to its various pharmacological activities. This review is the first to comprehensively summarize the current studies on pharmacokinetics profiles, pharmacological properties, and toxicological risks of DHE in diverse diseases. Pharmacokinetic studies have shown that DHE has a relatively good oral absorption effect in the mean concentration curves in rat plasma and high absorption in the gastrointestinal tract. In addition, distribution re-absorption and enterohepatic circulation may lead to multiple blood concentration peaks of DHE in rat plasma. DHE possesses a wide spectrum of pharmacological properties in the central nervous system, cardiovascular system, and digestive system. Moreover, DHE has anti-inflammatory effects
via
downregulating pro-inflammatory cytokines and inflammatory mediators. Given the favorable pharmacological activity, DHE is expected to be a potential drug candidate for the treatment of Alzheimer’s disease, chronic stress, amnesia, chronic atrophic gastritis, gastric ulcers, and rheumatoid arthritis. In addition, toxicity studies have suggested that DHE has proarrhythmic effects and can impair bile acid homeostasis without causing hepatotoxicity. However, further rigorous and well-designed studies are needed to elucidate the pharmacokinetics, pharmacological effects, potential biological mechanisms, and toxicity of DHE.
Sea ice is a complex media composed of discrete interacting elements of various sizes and thicknesses (floes), and at sufficiently small lengthscales it can not be approximated as a continuous media ...as routinely done at large scales. While the Eulerian data assimilation is a relatively mature field, techniques for assimilation of satellite‐derived Lagrangian trajectories of sea ice floes remain poorly explored. Here, an idealized discrete element sea ice model is developed and used as a testbed to quantify the efficacy of the minimum approximation for the Lagrangian data assimilation in an one‐way coupled ice‐ocean system. First, it is shown that observations of O(100) floes in a 50 km by 50 km domain are needed to achieve a high data assimilation accuracy, with a large observational timestep of 1 day being sufficient to recover the geophysically balanced part of the unobserved ocean flow, while about a 2‐h timestep is necessary to recover the unbalanced flows. Second, a simple stochastic parameterization is shown to improve the assimilation accuracy when only a small subset of floes is observed or there is a significant model error resulting for example from simplifying the collision laws between floes. Finally, an efficient expectation‐maximization algorithm is developed that succeeds in assimilating the ocean flow and simultaneously estimating individual floe thicknesses and the overall thickness distribution function. Our study implies that the minimum approximation with its closed analytical formulae could potentially provide an efficient data assimilation scheme for satellite observations of sea ice floes.
Plain Language Summary
Due to a strong demand on the state estimation of the sea ice, a discrete element model is developed and used as a testbed to quantify the efficacy of the minimum approximation for the Lagrangian data assimilation in a coupled ice‐ocean system. First, it is shown that observations of about 100 floes in a 50 km by 50 km domain can achieve a high data assimilation accuracy for recovering the geophysically balanced part of the unobserved ocean flow using a large observational timestep of 1 day. But a 2‐h timestep is needed to recover the unbalanced part of the ocean flows. Second, a simple approximation strategy is developed, which utilizes stochastic tools to improve the data assimilation. This new strategy is particularly useful if the system has large uncertainties when only a small subset of floes is observed or the collision laws between floes are simplified. Finally, an efficient algorithm is developed that assimilates the ocean flow and estimates individual floe thicknesses simultaneously. It also succeeds in recovering the overall thickness distribution function. Our study implies that the minimum approximation with its closed analytical formulae could potentially provide an efficient data assimilation scheme with the satellite observations of ice floes.
Key Points
An efficient Lagrangian data assimilation method is developed based on an idealized discrete element sea ice model
The method is highly accurate in recovering the unobserved balanced part of the ocean flow with large practical observational timestep
An expectation‐maximization algorithm is developed to estimate individual floe thicknesses based on the assimilated floe velocities
Aberrant activation of NLRP3 inflammasome has been implicated in the pathogenesis of diverse inflammation-related diseases, and pharmacological molecules targeting NLRP3 inflammasome are of ...considerable value to identifying potential therapeutic interventions. Cardamonin (CDN), the major active ingredient of the traditional Chinese medicinal herb
, has exerted an excellent anti-inflammatory activity, but the mechanism underlying this role is not fully understood. Here, we show that CDN blocks canonical and noncanonical NLRP3 inflammasome activation triggered by multiple stimuli. Moreover, the suppression of CDN on inflammasome activation is specific to NLRP3, not to NLRC4 or AIM2 inflammasome. Besides, the inhibitory effect is not dependent on the expression of NF-
B-mediated inflammasome precursor proteins. We also demonstrate that CDN suppresses the NLRP3 inflammasome through blocking ASC oligomerization and speckle formation in a dose-dependent manner. Importantly, CDN improves the survival of mice suffering from lethal septic shock and attenuates IL-1
production induced by LPS
, which is shown to be NLRP3 dependent. In conclusion, our results identify CDN as a broad-spectrum and specific inhibitor of NLRP3 inflammasome and a candidate therapeutic drug for treating NLRP3 inflammasome-driven diseases.
Aberrant activation of inflammasomes, a group of protein complexes, is pathogenic in a variety of metabolic and inflammation-related diseases. Here, we report that carnosol inhibits NLRP3 ...inflammasome activation by directly targeting heat-shock protein 90 (HSP90), which is essential for NLRP3 inflammasome activity, thereby treating inflammasome-mediated diseases. Our data demonstrate that carnosol inhibits NLRP3 inflammasome activation in primary mouse bone marrow-derived macrophages (BMDMs), THP-1 cells and human peripheral blood mononuclear cells (hPBMCs). Mechanistically, carnosol inhibits inflammasome activation by binding to HSP90 and then inhibiting its ATPase activity. In vivo, our results show that carnosol has remarkable therapeutic effects in mouse models of NLRP3 inflammasome-mediated diseases, including endotoxemia and nonalcoholic steatohepatitis (NASH). Our data also suggest that intraperitoneal administration of carnosol (120 mg/kg) once daily for two weeks is well tolerated in mice. Thus, our study reveals the inhibitory effect of carnosol on inflammasome activation and demonstrates that carnosol is a safe and effective candidate for the treatment of inflammasome-mediated diseases.
Aberrant activation of NLRP3 inflammasome has been implicated in a variety of human inflammatory diseases, but currently, no pharmacological NLRP3 inhibitor has been approved. In this study, we ...showed that echinatin, the ingredient of the traditional herbal medicine licorice, effectively suppresses the activation of NLRP3 inflammasome in vitro and in vivo. Further investigation revealed that echinatin exerts its inhibitory effect on NLRP3 inflammasome by binding to heat-shock protein 90 (HSP90), inhibiting its ATPase activity and disrupting the association between the cochaperone SGT1 and HSP90-NLRP3. Importantly, in vivo experiments demonstrated that administration of echinatin obviously inhibits NLRP3 inflammasome activation and ameliorates LPS-induced septic shock and dextran sodium sulfate-induced (DSS-induced) colitis in mice. Moreover, echinatin exerted favorable pharmacological effects on liver inflammation and fibrosis in a mouse model of nonalcoholic steatohepatitis (NASH). Collectively, our study identifies echinatin as a potentially novel inhibitor of NLRP3 inflammasome, and its use may be developed as a therapeutic approach for the treatment of NLRP3-driven diseases.
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