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Reduced graphene oxide (rGO) has attracted wide attention as anode materials of lithium ion batteries, however, restacking of rGO sheets limits its capacity and rate performance. To address this issue, a sandwich-like composite of N-doped carbon (NDC) and rGO (rGO@NDC) was fabricated via a process of absorbing [EMIm]N(CN) 2 ionic liquid on the surface of graphene oxide (GO) nanosheets and subsequent heat-treating of the composite. The rGO@NDC composite exhibits a high specific capacity of 409.4 mAh g−1 with a Coulombic efficiency of 100% after 50 cycles at a charge-discharge rate of 0.5 C, and a specific capacity of 222.8 mAh g−1 with no capacity fade after 1200 cycles at charge-discharge rate of 10 C. Compositing the rGO with NDC particles can decrease the superficial oxygen-containing functional groups of the rGO, and therefore decrease side reactions during battery cycling. And embedding of NDC particles on the surface of rGO sheets avoids the restacking of rGO sheets and enlarges the interlayer space of the rGO to facilitate Li+ transport within the rGO@NDC. Finally, the NDC particles provide more accessible sites for Li+, and rGO sheets as conductivity networks improves electron transport. [ABSTRACT FROM AUTHOR]

• NMM is enhanced to simulate crack initiation, propagation and coalescence. • Four typical brittle cracking examples under dynamic loading are well simulated. • Mesh size, wave propagation, crack propagation velocity, etc. are analyzed. • Effects of pre-existing geometrical defects (hole and notch) are analyzed. Crack development in brittle materials under dynamic loading is widely involved in engineering, in which crack initiation, propagation and coalescence are typical phenomena. The numerical manifold method (NMM) is a unified continuous-discontinuous numerical method employing two cover systems, namely, mathematical covers and physical covers, which encounters no difficulty in the numerical representation of continua and complex discontinuities within one framework. In the present work, NMM is developed for the simulation of crack initiation, propagation and coalescence problems in brittle materials under dynamic loading based on the tensile strength criterion and the Mohr-Coulomb strength criterion for tensile and shear cracking, respectively. Four typical examples including the splitting of a rock bar, the Kalthoff-Winkler experiment, the cracking in tensile loaded pre-notched rectangular plates and the double-hole blasting of rectangular plates are simulated. The numerically derived crack development results are compared with corresponding theoretical or experimental results. The mesh size sensitivity is discussed for the first two examples; the dynamic cracking mechanism in the rock bar example is investigated along with the stress wave propagation analysis; the influence of the initial crack and hole locations on the crack path in the tensile loaded pre-notched example as well as the effect of the guiding notch in the double-hole blasting example are studied. Results indicate that the crack initiation, propagation and coalescence in brittle materials under dynamic loading are quite satisfactorily reproduced by NMM. [ABSTRACT FROM AUTHOR]

[Display omitted] • Glutamate can enhance the growth performance of piglets. • Glutamate can enhance immunity of piglets. • Glutamate can improve intestinal immunity by modulating gut microbiota and Th17/Treg balance-related signaling pathways. The purpose of this study was to explore the effects of glutamate on piglet growth performance and intestinal immunity function, and to further elucidate its mechanism. In a 2 × 2 factorial design involving immunological challenge (lipopolysaccharide (LPS) or saline) and diet (with or without glutamate), twenty-four piglets were randomly assigned to four groups, each with 6 replicates. Piglets were fed with a basal or glutamate diet for 21 d before being injected intraperitoneally with LPS or saline. Piglet's intestinal samples were collected 4 h after injection. Results showed that glutamate increased daily feed intake, average daily gain, villus length, villus area, and villus length to crypt depth ratio (V/C), and decreased the crypt depth (P < 0.05). Furthermore, glutamate increased the mRNA expression of forkhead box P3 (FOXP3), a signal transducer and activator of transcription 5 (STAT5) and transforming growth factor beta, while decreasing the mRNA expression of RAR-related orphan receptor c and STAT3. Glutamate increased interleukin-10 (IL-10) mRNA expression while decreasing the mRNA expression of IL-1β, IL-6, IL-8, IL-17, IL-21, and tumor necrosis factor-α. At the phylum level, glutamate increased the Actinobacteriota abundance and Firmicutes -to- Bacteroidetes ratio while decreasing Firmicutes abundance. At the genus level, glutamate improved the abundance of beneficial bacteria (e.g., Lactobacillus , Prevotellaceae-NK3B31-group, and UCG-005). Furthermore, glutamate increased the concentrations of short-chain fatty acids (SCFAs). Correlation analysis revealed that the intestinal microbiota is closely related to Th17/Treg balance-related index and SCFAs. Collectively, glutamate can improve piglet growth performance and intestinal immunity by modulating gut microbiota and Th17/Treg balance-related signaling pathways. [ABSTRACT FROM AUTHOR]

• A sub-block element DDA method is applied and verified for the simulations crack initiation, propagation, and coalescence in brittle materials. • Examples including the Kalthoff-Winkler experiment, the cracking in a tensile loaded plate, and the double-hole blasting of a rectangular plate are reproduced. • Problems including the mesh size, loading intensity, crack propagation velocity, and the effect of guiding hole are investigated. Cracking in brittle materials under dynamic loading is widely encountered in engineering. The discontinuous deformation analysis (DDA) is a numerical method initially proposed to calculate the static and dynamic behaviors of discrete deformable-block systems, which can also be used to simulate the cracking failure of materials via the sub-block element approach. In the present work, a sub-block element DDA method is applied to simulate the crack evolution problems in brittle materials under dynamic loading. The tensile and shear cracking along the artificial joints between glued sub-block elements is judged based on the stress levels of adjacent sub-blocks by the maximum tensile strength criterion and the Mohr-Coulomb criterion, respectively. Three numerical examples including the Kalthoff-Winkler experiment, the cracking in a tensile loaded plate and the double-hole blasting of a rectangular plate are simulated. The effect of the mesh size for the Kalthoff-Winkler experiment, the loading intensity for the Kalthoff-Winkler experiment and the tensile loaded plate, and the influence of the guiding hole for the double-hole blasting plate are specially investigated. The DDA simulation results of cracking routes and velocity are reasonably consistent with the corresponding experimental results or numerical results by other methods, which manifests the ability of the applied sub-block element DDA method in the simulations crack propagation, branching and coalescence of brittle materials under dynamic loading. [ABSTRACT FROM AUTHOR]

Suicide is a major public health problem affecting US Veterans and the US in general. Many variables (e.g., demographic, clinical, biological, geographic) have been associated with risk for suicide and suicidal behavior, including altitude; however, the exact nature of the relationship between altitude and suicide remains unclear in part due to the fact that previous studies have used either geospatial data or individual-level data, but not both. Prior research has also failed to consider the full range of suicidal thoughts and behaviors, ranging from suicidal ideation to suicide deaths. Accordingly, the objective of the present research was to use both geospatial data (county and zip codes) and individual-level data to comprehensively assess the association between altitude and suicide mortality, suicide attempts, and suicidal ideation among US Veterans between 2000 and 2018. Taken together, our results demonstrate that there is a strong correlation between altitude and suicide rates at all the levels investigated and using different statistical analyses and even after controlling for significant covariates such as percent of age >50yr, percent male, percent white, percent non-Hispanic, median household income, and population density. We show that there is a positive correlation between altitude and suicide attempts especially when controlling by the covariates and a weak correlation between altitude and suicide ideation and the combination of suicide, suicide attempts and suicide ideation. • There is a significant correlation between altitude and suicide mortality rate for U.S. veterans. • The association between altitude and suicide deaths is higher than the association with suicide attempts or ideation. • Controlling for relevant factors improves the correlation. [ABSTRACT FROM AUTHOR]

Variations in systemic inflammatory response biomarker levels have been associated with adverse clinical outcome in various malignancies. In this study, we aimed to evaluate the predictive and prognostic role of the pretreatment neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in cervical cancer. We retrospectively investigated 616 patients who underwent initial radical hysterectomy with pelvic lymphadenectomy for cervical cancer between July 2012 and December 2014 in China. Their clinical and histopathological markers and complete blood counts were obtained and analyzed. Then we chose the group of 339 of the total 616 patients who were not combined preoperative radiotherapy or chemotherapy for the survival analysis. Prognostic factors were assessed by univariate and multivariate analyses. The ROC curve revealed NLR and PLR had significant ability to predict parametrial involvement, and the cutoff values for NLR and PLR were 2.5 and 138.8 respectively. Clinicopathologic analysis showed that NLR was linked to age, parametrial involvement, tumor-invasion depth and histologic grade, and PLR was related to age, parametrial involvement, tumor-invasion depth and FIGO stage. Univariate analysis identified high PLR as a significant poor predictor for progression-free survival (PFS) and overall survival (OS), and NLR exhibited no predict power on OS or PFS. Multivariable analysis showed that PLR was an independent predictor of PFS, but not OS. NLR and PLR were associated with the clinical characteristics of cervical cancer. Additionally, PLR had independence prognostic value for PFS in patients with cervical cancer receiving radical hysterectomy with pelvic lymphadenectomy. [ABSTRACT FROM AUTHOR]