Both inflammatory processes and glutamatergic systems have been implicated in the pathophysiology of mood-related disorders. However, the role of caspase-1, a classic inflammatory caspase, in ...behavioral responses to chronic stress remains largely unknown. To address this issue, we examined the effects and underlying mechanisms of caspase-1 on preclinical murine models of depression. We found that loss of caspase-1 expression in Caspase-1
knockout mice alleviated chronic stress-induced depression-like behaviors, whereas overexpression of caspase-1 in the hippocampus of wild-type (WT) mice was sufficient to induce depression- and anxiety-like behaviors. Furthermore, chronic stress reduced glutamatergic neurotransmission and decreased surface expression of glutamate receptors in hippocampal pyramidal neurons of WT mice, but not Caspase-1
mice. Importantly, pharmacological inhibition of caspase-1-interleukin-1β (IL-1β) signaling pathway prevented the depression-like behaviors and the decrease in surface expression of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) in stressed WT mice. Finally, the effects of chronic stress on both depression- and anxiety-like behaviors can be mimicked by exogenous intracerebroventricular (i.c.v.) administration of IL-1β in both WT and Caspase-1
mice. Taken together, our findings demonstrate that an increase in the caspase-1/IL-1β axis facilitates AMPAR internalization in the hippocampus, which dysregulates glutamatergic synaptic transmission, eventually resulting in depression-like behaviors. These results may represent an endophenotype for chronic stress-induced depression.
The glass forming ability (GFA) is a problem of great concern in the research of amorphous materials. It is of great significance to understand the physical mechanism of GFA and to seek conditions ...and methods to improve it. In this study, we collected 820 experimental data from existing literature, and used gradient boosted decision trees (GBDT) model to predict the GFA. The GBDT model optimized by 10-fold cross-validation and grid search technology shows excellent predictive results. The determination coefficient (R2) and root mean square error (RMSE) are 0.652 and 2.85, respectively. Compared with the previously reported 27 criteria and ML models, GBDT model has the highest prediction ability. The result exhibit that the predictive performance of GBDT can be significantly improved by considering the atomic size difference, total electronegativity, mixing entropy and average atomic volume.
•The GBDT model for predicting the GFA of amorphous alloys was developed.•Grid-search and cross-validation were used to determine the hyperparameters.•The GBDT model provides the highest accuracy in GFA prediction.•The predictive performance of GFA can be significantly improved after adding TEN, δ, VA and Sm.
Fluid–structure interaction (FSI) problems with large fluid deformations can be a great challenge for numerical simulations using conventional methods. In this paper, we propose a novel hybrid ...approach of an improved Smoothed Particle hydrodynamics and smoothed finite Element Method (SPEM) for modeling FSI problems. In SPEM, the edge-based smoothed finite element method (S-FEM) is developed in Lagrangian frame and is used for the first time to model both elastic structures and incompressible flows. For fluid regions with large deformations, the associated finite elements are adaptively converted into particles and the corresponding regions are subsequently modeled using the decoupled finite particle method (DFPM), which is an improved smoothed particle hydrodynamics (SPH) method suitable for modeling incompressible flows with free surfaces. A ghost particle-based interface algorithm to couple existing S-FEM elements and DFPM particles is developed in SPEM to implement the modeling of FSI problems. As the smoothed FEM and decoupled FPM are enhanced FEM and SPH respectively and DFPM is only used for local fluid regions with large deformations, it is expected that SPEM is more accurate and more efficient than the existing coupling approaches of conventional FEM and SPH. Five numerical examples are tested using the proposed SPEM and the comparative studies with results from other sources reveal that SPEM is an effective approach for modeling FSI problems with large fluid deformations.
•A smoothed particle element method (SPEM) is developed for modeling fluid–structure interactions.•The Lagrangian smoothed FEM (S-FEM) is used for modeling both structures and fluids.•The decoupled finite particle method (DFPM) is employed to model fluid regions with large deformations.•A ghost particle-based interface algorithm is developed to couple S-FEM and DFPM.•SPEM is more accurate and efficient than existing FEM-SPH or pure SPH approaches.
Desulfovibrio spp. is predominant member of sulphate‐reducing bacteria in human gut microbiota. Previous studies indicated that the isolation of Desulfovibrio strains from human faecal samples is ...very important to study the roles of human intestinal Desulfovibrio spp. in maintaining healthy states or causing diseases, as well as defining their biological characteristics. However, there are very few reports describing the isolation of Desulfovibrio spp. from human faecal samples. In this study, faecal samples were inoculated into various media containing different components. The enriched culture communities were identified using 16S rRNA gene high‐throughput sequencing analysis, enabling us to identify the specific components that enable the enrichment of Desulfovibrio. Using this information, we developed five specific media and identified an effective enrichment medium that produced the highest relative abundance of Desulfovibrio in communities cultured from four faecal samples (26·5, 73·5, 44·7 and 77·6% respectively). In addition, the major non‐Desulfovibrio genera were identified. Finally, three species of Desulfovibrio, D. desulfuricans, D. piger and D. legallii were isolated, representing the first time that has D. legallii been isolated from a human gastrointestinal source.
Significance and Impact of the Study
ost of the human intestinal bacteria have not been cultured because of lack of appropriate culture method and appropriate media. Desulfovibrio spp. is associated with several clinical conditions like inflammatory bowel disease, but until now there are very few reports describing the isolation of Desulfovibrio spp. from human faecal samples. In this study, 16S rRNA gene high‐throughput sequencing analysis was applied to screen appropriate enrichment media and selective cultivation of Desulfovibrio. This sequencing‐based directed culture method described here can be used for the selective cultivation of gut bacteria of interest.
Significance and Impact of the Study: Most of the human intestinal bacteria have not been cultured because of lack of appropriate culture method and appropriate media. Desulfovibrio spp. is associated with several clinical conditions like inflammatory bowel disease, but until now there are very few reports describing the isolation of Desulfovibrio spp. from human faecal samples. In this study, 16S rRNA gene high‐throughput sequencing analysis was applied to screen appropriate enrichment media and selective cultivation of Desulfovibrio. This sequencing‐based directed culture method described here can be used for the selective cultivation of gut bacteria of interest.
Randomized controlled trials (RCT) usually have strict implementation criteria. The included subjects' characteristics of the conditions for the intervention implementation are quite different from ...the actual clinical environment, resulting in discrepancies between the risk-benefit of interventions in actual clinical use and the risk-benefit shown in RCT. Therefore, some methods are needed to enhance the extrapolation of RCT results to evaluate the real effects of drugs in real people and clinical practice settings.
Six databases (PubMed, Embase, Web of Science, CNKI, Wanfang Data, and VIP) were searched up to 31
December 2022 with detailed search strategies. A scoping review method was used to integrate and qualitatively describe the included literature inductively.
A total of 12 articles were included. Three methods in the included literature focused on: ①improving the design of traditional RCT to increase population representation; ②combining RCT Data with real-world data (RWD) for analysis;③calibrating RC
Sedum alfredii Hance has been identified as a new zinc (Zn) hyperaccumulating plant species. In this study, the effects of cadmium (Cd) supply levels (control, 12.5, 25, 50, 100, 200, 400, 800 μmol ...Cd L-1) on the growth and cadmium accumulation and Zn supply on Cd accumulation in S. alfredii Hance were studied. The results showed that no reduction in shoot and root dry matter yields were noted when the plants were grown at Cd supply levels up to 200 μmol L-1 in nutrient solution. Slight stimulation on shoot growth was noted at relatively low Cd levels (25 to 100 μmol L-1). Cadmium concentrations in leaves and stems increased with increasing Cd supply levels, and reached a maximum of approximately 9000 and 6500 mg kg-1 (DW) at 400 μmol Cd L-1, respectively. Root Cd concentration increased sharply only at relatively high Cd levels. Cadmium distribution in different parts of the plant was in the order: leaf > stem >> root. The amount of Cd accumulated in the shoots reached 2.9 and 3.2 mg plant-1 at external Cd levels of 200 and 400 μmol L-1, respectively. The shoot/root Cd ratios were greater than 2 and more than 95% of the total Cd taken up by S. alfredii was translocated to the shoots at the external Cd levels ≤200 μmol L-1. The concentrations of P, Ca, Mg, B, Fe, Mn, Cu, and in the shoots and roots were influenced differentially by Cd treatments. High Zn supply (500 μmol L-1) enhanced Cd concentrations in the leaves and stems at the Cd levels ≤100 μmol L-1, and root Cd concentration at the Cd levels ≤50 μmol L-1. These results indicate that S. alfredii has an extraordinary ability to tolerate and hyperaccumulate Cd and this is the first report of the new Cd hyperaccumulator S. alfredii Hance. The finding of Cd/Zn hyperaccumulation in S. alfredii Hance provides an important plant material for understanding the mechanisms of Cd/Zn co-hyperaccumulation and for phytoremediation of the heavy metal contaminated soils.
The cyclic quenching with both the rapid heating and cooling was applied on 51CrV4 spring steels by a DIL805A/D dilatometer. The microstructures were observed by a scanning electron microscope (SEM) ...and a transmission electron microscope (TEM), whereas the strengthening mechanism of the test steels was discussed by the general equation of Rp0.2i=σ0+Δσpi+Δσri+ΔσTi. The results demonstrated that the grain size was the lowest with only 1.76µm, the area fraction of the twins was the highest up to 6.78% and the thickness of the twins was fined to 11.71nm at six times. Also, an excellent comprehensive performance was obtained, such as the yield strength, the tensile strength and the area reduction of the test steels was increased substantially as the cyclic quenching was conducted from 1 to 6 times, where the maximum values were up to 1792.93MPa, 2036.2MPa and 44%, respectively. As a result, the strength increase was mainly attributed to the ultra-refine grain formation, the area fraction increase of the micro-nano scale twins and the size refinement decrease; whereas it was observed that the highest contribution to the strength and ductility was from the micro-nano scale twins.
Traditional reliability-based design optimization (RBDO) generally describes uncertain variables using random distributions, while some crucial distribution parameters in practical engineering ...problems can only be given intervals rather than precise values due to the limited information. Then, an important probability-interval hybrid reliability problem emerged. For uncertain problems in which interval variables are included in probability distribution functions of the random parameters, this paper establishes a hybrid reliability optimization design model and the corresponding efficient decoupling algorithm, which aims to provide an effective computational tool for reliability design of many complex structures. The reliability of an inner constraint is an interval since the interval distribution parameters are involved; this paper thus establishes the probability constraint using the lower bound of the reliability degree which ensures a safety design of the structure. An approximate reliability analysis method is given to avoid the time-consuming multivariable optimization of the inner hybrid reliability analysis. By using an incremental shifting vector (ISV) technique, the nested optimization problem involved in RBDO is converted into an efficient sequential iterative process of the deterministic design optimization and the hybrid reliability analysis. Three numerical examples are presented to verify the proposed method, which include one simple problem with explicit expression and two complex practical applications.
Liquid sloshing flows interacting with deformable structures are difficult to be numerically simulated due to the co-existence of moving fluid-structure interfaces and breaking free surfaces. As a ...Lagrangian and particle-based method, the smoothed particle hydrodynamics (SPH) method has natural advantages in handling free-surface flows. The smoothed finite element method (SFEM) provides a reliable tool to capture the associated structural deformations, and it can solve the “overly-stiff” problem in the conventional FEM. In this work, the coupling strategy of an improved SPH version and SFEM is integrated with advanced fluid modeling techniques, and is extended and validated for modeling liquid sloshing with rigid or deformable structures. Both the rigid wall boundaries and deformable structures are reproduced by the elements, whereas the fluid particles with a different resolution can be adopted. The integrated δ-SPH model can significantly alleviate the spurious high-frequency noise of the computed impact pressure in a sloshing process. The particle shifting technique helps improve both accuracy and robustness of the fluid flow model. The virtual particle coupling strategy is effective to transfer information between SPH particles and SFEM elements. Various numerical tests show that the present coupling approach is very effective for modeling violent sloshing with deformable baffles or deformable container walls. This method is more accurate than the conventional coupling of SPH-FEM and can obtain results very close to the experimental observations compared with some numerical approaches from other sources.
Abstract
This study proposed a long short-term memory (LSTM) model for predicting the serrated flow behaviors of bulk metallic glasses (BMGs) under nanoindentation. A series of load-controlled ...nanoindentation tests were conducted on a Pd
40
Cu
30
Ni
10
P
20
BMG. The LSTM model was introduced to establish a neural network for predicting the serrated flow at different loading rates, and was verified by the comparisons of experimental data with predictive results. Further investigation based on the predictive serrated flows under different loading rates showed that the serrations exhibit a significant self-organized critical (SOC) phenomenon at different loading rates. The SOC phenomena of the serrations under a lower loading rate were more obvious than that under a higher loading rate.
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