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Abstract Photon emission may be continuously produced from mechanical work through self-recoverable mechanoluminescence (ML). Significant progress has been made in high-performance ML materials in the past decades, but the rate-dependent ML kinetics remains poorly understood. Here, we have conducted systematic studies on the self-recoverable ML of Mn2+-doped SrZnOS (SrZnOS: Mn2+) under rapid compression up to ~10 GPa. Rate-dependent distinct kinetics is revealed: a diffuse-like ML behavior below ~1.2 GPa/s, oscillatory emission with a series of ML peaks at critical rate of ~1.2–1.5 GPa/s, and suppression of ML above 1.5 GPa/s. Analysis from the rate-independent structural evolution and photoluminescence under high pressures show that the oscillatory ML emission at the critical rate corresponds to multi-cyclic piezoelectrically-induced excitation (PIE) and self-recoverable processes. Both characteristic time (τ) for the PIE and self-recoverable processes are minimized at the critical rate, indicating the time limit of ML in the dynamic response to rapid compression. High temperature is slightly favorable for PIE, but is unfavorable for the self-recoverable process. The present work uncovers the temporal characteristics of self-recoverable ML and provides insight into understanding the rate-dependent ML kinetics in the mechanical-photon energy conversion, conducive to the design of ML-based optoelectronic devices.

Lanthanum lithium titanate is one of the promising electrolytes for solid-state lithium-ion batteries due to its high bulk ionic conductivity up to ∼10−3 S/cm. However, the practical application of this material has been bottlenecked by high grain boundary (GB) resistance, while the underlying mechanism is still under debate. Here we report a comprehensive study with direct evidence to reveal the origin of high GB resistance in La2/3–xLi3xTiO3 (LLTO). Atomic-scale observations via advanced scanning transmission electron microscopy show that the GBs are uniformly subject to subsurface segregation of La atoms to compensate for the excess surface charges. The La segregation leads to an abrupt decrease of charge carrier concentration neighboring GBs and hence is supposed to have deleterious effect on GB conductivity. The findings suggest a novel mechanism of space-charge-induced cation segregation, which shed lights on the intrinsic origin of low GB ionic conductivity in LLTO.

This study is to probe into the meaning of serum miR-532-5p in nontraumatic osteonecrosis of the femoral head (ONFH), and a molecular mechanism of miR-532-5p in the development of nontraumatic ONFH. This study enrolled 96 patients diagnosed with nontraumatic ONFH and 96 patients with femoral neck fracture. The levels of miR-532-5p, ABL1, MMP-3, MMP-13, and cleaved-caspase3 were determined. Radiographic progression was assessed by ARCO staging system. Visual analog scale (VAS) and Harris hip score (HHS) were employed for evaluation of the symptomatic severity of nontraumatic ONFH. Cell viability and apoptosis in chondrocytes isolated from clinical samples were investigated with CCK-8 and flow cytometry. The levels of lactic dehydrogenase (LDH), superoxide dismutase (SOD), and malondialdehyde (MDA), mitochondrial membrane potential (ΔΨm), and reactive oxygen species (ROS) were determined. miR-532-5p was downregulated in tissues and serum of patients with nontraumatic ONFH, negatively related with ARCO staging and VAS, and positively correlated with HHS. Cell apoptosis, LDH, MDA, and ROS strengthened, while cell viability, ΔΨm, and SOD reduced in chondrocytes of nontraumatic ONFH patients. ABL1 was upregulated in cartilage tissues from nontraumatic ONFH patients. miR-532-5p targeted ABL1, and overexpressed miR-532-5p alleviated nontraumatic ONFH-induced oxidative stress damage of chondrocytes by restraining ABL1. miR-532-5p ameliorated oxidative stress injury in nontraumatic ONFH by inhibiting ABL1.

BackgroundThe direct simulation of the γ radiation field in a large space has a very low calculation efficiency.PurposeThis study aims to apply the global variance reduction (GVR) method to the calculation of the γ radiation field in a large space.MethodsFirstly, the volume correction factor was introduced for modifying the lower limit of the weight window wth to address the over-splitting problem caused by the volume difference between the counting cells/grids. The global quality factor (FOMG factor) calculated by the flux-based GVR method using the volume correction was 39 times higher than that obtained by direct simulation. Then, a non-counting area correction method was proposed to address the time-consuming problem encountered in non-counting area calculation while the FOMG factor was further improved by 40%. Finally, based on both the volume correction and non-counting area correction, the calculation of the γ radiation field were compared with that of seven GVR methods based on the particle error, weight, track, number, energy, collision and flux, respectively. The smoothing factor SI was introduced into the flux-based GVR method for results further analysis. [Results and Conclusions] The results show that the FOMG factor calculated by the seven GVR methods is about 2~3 orders of magnitude higher than that obtained by direct simulation, and the standard deviation σ is reduced by 2~3 orders of magnitude. The FOMG factor calculated by the weight-based GVR method is 2 304 times higher than that obtained by direct simulation; this value yields the best variance reduction effect among all GVR methods. As SI increases, the lower limit of the weight window wth of the simulation decreases, and the FOMG factor first increases and then decreases. When SI=0.8, the calculated FOMG factor has the largest value, which is 3 246 times higher than that obtained by direct simulation.

Objectives This systematic review and meta-analysis examined whether the lymphocyte-to-monocyte ratio (LMR) can serve as an indicator for predicting the prognosis of patients with resectable pancreatic cancer. Patients and Methods This meta-analysis was registered with PROSPERO: CRD42023461260. A systematic literature search was conducted in the PubMed, Embase, Cochrane, and Web of Science databases up to September 2023 to assess whether LMR can predict the prognosis of patients with resectable pancreatic cancer. The outcomes measured included subgroup analyses of overall survival (OS) with hazard ratios (HR) and confidence intervals of geographical region, patient population, and LMR threshold. A sensitivity analysis was also performed for OS and HR and confidence intervals were calculated for recurrence-free survival (RFS). Results A total of 14 eligible articles, comprising 4,019 patients, were included in the comprehensive analysis. The results of this comprehensive analysis indicate that LMR is a robust predictor of OS, demonstrating strong prognostic significance (HR = 0.55, 95% CI [0.44–0.69], I2 = 79%, P < 0.00001). This predictive significance extended to various types of pancreatic cancer, such as pancreatic ductal adenocarcinoma (HR = 0.73, 95% CI [0.57–0.93], I2 = 46%, P = 0.01), pancreatic neuroendocrine neoplasms (HR = 0.81, 95% CI [0.66–0.99], P = 0.04) and other subtypes (HR = 0.40, 95% CI [0.22–0.72], I2 = 89%, P < 0.00001), but not to pancreatic head cancer (HR = 0.46, 95% CI [0.16–1.13], I2 = 59%, P = 0.12). LMR retained its predictive value across different regions, including Asia (HR = 0.62, 95% CI [0.47–0.76], I2 = 68%, P < 0.0001), Europe (HR = 0.78, 95% CI [0.67–0.91], I2 = 0%, P = 0.002), and the Americas (HR = 0.14, 95% CI [0.08–0.24], I2 = 0%, P < 0.00001). Notably, both LMR cut-off values greater than or equal to three (HR = 0.62, 95% CI [0.47–0.82], I2 = 67%, P = 0.0009) and less than three (HR = 0.47, 95% CI [0.32–0.69], I2 = 85%, P = 0.0001) exhibited prognostic significance. The sensitivity analysis for OS confirmed the strong predictive value of LMR, whereas LMR did not exhibit predictive significance for RFS (HR = 0.35, 95% CI [0.09–1.32], I2 = 95%, P = 0.12). In both subgroups categorized by Newcastle-Ottawa Scale (NOS) scores of ≥7 (HR = 0.66, 95% CI [0.54–0.80], I2 = 53%, P = 0.04) and

Aiming at the problems of insufficient modeling accuracy and low efficiency of design verification and calculation in the current parametric design and development of internal gears, a parametric design system of internal gears based on accurate tooth profile modeling is developed by using Matlab GUI. According to the principle of gear generating machining theory, the involute tooth profile of internal gears is generated. The tooth profile-normal method is used to establish the tooth root transition curve equation of internal gears, realizing the accurate modeling of the whole tooth of internal gears, and the pressure angles αM and αN at the transition point of the internal gear profile are calculated. The geometric calculation and interference verification of the design parameters of internal gear pairs are completed through the parametric design program. In the transition curve interference verification part, using the pressure angles αM and αN of the tooth profile transition point, the verification formula of the transition curve interference of the internal gear pair is calculated under the condition of any size tooth top fillet (or unspecified fillet) of the cutter. Finally, the whole tooth profile data of the designed target gear pairs is imported into the Catia interface, and the three-dimensional solid model of the gear pairs is established, which lays a foundation for the subsequent research on the stress analysis and dynamic performance detection of the gear system.

Abstract Oxygen deficiency has crucial effects on the crystal structure and electrochemical performance of spinel oxide lithium electrode materials such as LiNi0.5Mn1.5O4 (LNMO) cathode. In particular, the oxygen stoichiometry on the crystal surface differs from that on the crystal interior in LNMO. The detection of local oxygen loss in LNMO and its correlation with the crystal structure and the cycling stability of LNMO remain challenging. In this study, the effect of oxygen deficiency in LNMO controlled by sintering temperature on the surface crystal structure and electrochemical performance of LNMO is comprehensively investigated. The high concentration of oxygen vacancies segregates at the surface regions of LNMO forming a thin rock‐salt and/or deficient spinel surface layer. The atomic‐level surface structure reconstruction was demonstrated by annular dark‐field and annular bright‐field techniques. For the synthesis of LNMO, the higher sintering temperature results in higher crystallinity but the higher oxygen deficiency in LNMO. The high crystallinity of LNMO would increase the thermal stability of LNMO cathodes while the high content of oxygen deficiency would decrease the surface structural stability of LNMO. Therefore, the LNMO sintered at a medium temperature of 850°C achieved the best capacity retention. The results suggest a competitive function mechanism between oxygen stoichiometry and the crystallinity of LNMO on the cycling performance of LNMO.

Abstract Transparent conducting oxides (TCO) with high electrical conductivity and high visible light transparency are desired for a wide range of high‐impact engineering. Yet, usually, a compromise must be made between conductivity and transparency, limiting the practical application of a TCO to the next level. Furthermore, TCO performance is highly sensitive to composition, so conventional synthesis methods, such as chemical doping, cannot unravel the mysteries of the quantitative structure–performance relationship. Thus, improving the fundamental understanding or creating materials‐by‐design has limited success. Here, a strategy is proposed to modulate the lattice and electronic and optical properties precisely by applying pressure on a TCO. Strikingly, after compression–decompression treatment on the indium titanium oxides (ITiO), a highly transparent and metastable phase with two orders of magnitude enhancement in conductivity is synthesized from an irreversible phase transition. Moreover, this phase possesses previously unattainable filter efficiency on hazardous blue light up to 600 °C, providing potential for healthcare‐related applications with strong thermal stability up to 200 °C. These results demonstrate that pressure engineering is a clean and effective tool for tailoring functional materials that are not achievable by other means, providing an exciting alternative property‐tuning dimension in materials science.

The vibration is a main factor to influence the performance of chain drive. The difference between normal roller chains and constrained conveyor chains is that the main vibration mode of constrained trajectory conveyor chains is longitudinal. The model and its equivalent model are established to solve this problem.The kinetics model is built to resolve the natural frequency and principal mode based on the vibration theory of multiple-degree-of-freedom system. The dynamic response in one period is obtained based on the forced vibration theory of multiple-degree-of-freedom system. The analysis shows that the value of natural frequency of longitudinal vibration of constrained trajectory conveyor chains with long pitch is large and the vibration response in no-load operating condition is weak. In another word,the vibration is improved greatly with the constrained trajectory.

The conveyor chains bear a periodically impact loading due to the polygonal effect. The model of constrained trajectory of conveyor chains with long pitch is built toward this issue. The model is divided into two parts: chain wheel and top edge. The kinematics models of the two parts are established based on the Lagrange equation to calculate the generalized moment. In order to calculate the contact stress between the pins and other parts more precise,the models of chain wheel-pitch and pitch-pins are built by using the ABAQUS.The generalized moment is used to calculate the maximum contact stress and its position on pins. The consequence may provide some reference for the selection of material and the method of heat treatment.

Age-related macular degeneration (AMD) is the leading cause of blindness in elderly people, with limited treatment options available for most patients. AMD involves the death of retinal pigment epithelium (RPE) and photoreceptor cells, with mitochondria dysfunction being a critical early event. In the current study, we utilized our unique resource of human donor RPE graded for AMD presence and severity to investigate proteome-wide dysregulation involved in early AMD. Organelle-enriched fractions of RPE were isolated from donors with early AMD (n = 45) and healthy age-matched controls (n = 32) and were analyzed by UHR-IonStar, an integrated proteomics platform enabling reliable and in-depth proteomic quantification in large cohorts. A total of 5941 proteins were quantified with excellent analytical reproducibility, and with further informatics analysis, many biological functions and pathways were found to be significantly dysregulated in donor RPE samples with early AMD. Several of these directly pinpointed changes in mitochondrial functions, e.g., translation, ATP metabolic process, lipid homeostasis, and oxidative stress. These novel findings highlighted the value of our proteomics investigation by allowing a better understanding of the molecular mechanisms underlying early AMD onset and facilitating both treatment development and biomarker discovery.

This study aims to get the optimization neutron shielding design of iron/polyethylene combined shield structure. The neutron transmission coefficient with various energies for different thickness of iron and polyethylene combined shield structure were calculated by using Monte Carlo method. The simulation results show that the optimization effect of iron/polyethylene combined shield is not obvious when the neutron energy is low or the shield is thin, there is an optimal thickness ratio of iron to polyethylene adopted to get the best neutron shielding performance when the energy of neutron source is above 2 MeV and the total thickness of combined shielding structure is more than 20 cm. The optimal thickness ratio of iron to polyethylene increases with the increasing energy of neutron source; with the increasing of neutron source energy ranging from 4 MeV to 14 MeV, the optimal thickness ratio of iron to polyethylene trends from 0.11 to nearly 1.6.

Fourier transform infrared (FT-IR) spectroscopy has attracted great attention in the field of disease diagnostics for many years. Yet, the clinical translation of FT-IR spectroscopy has been rather slow because of several bottlenecks. This work explores the potential of aluminum foil-assisted attenuated total reflectance-FT-IR (ATR-FT-IR) spectroscopy, which is a simple and economical FT-IR sampling technique, to detect acute kidney injury (AKI) induced by gentamicin in a rat model. It was found that partial least squares-discriminant analysis (PLS-DA) could successfully discriminate between the AKI status and the healthy status with the plasma samples of the rats. An in-depth discussion on the advantages of aluminum-foil-assisted ATR-FT-IR spectroscopy in FT-IR-based disease diagnostics is also provided., Fourier transform infrared (FT-IR) spectroscopy is a rapid, non-invasive, and label-free analytical technology and has attracted great attention in the field of disease diagnostics for many years (1-6). As a [...]

Abstract Background CD147 plays a critical role in the invasive and metastatic activity of hepatocellular carcinoma (HCC) cells by stimulating the surrounding fibroblasts to express matrix metalloproteinases (MMPs). Tumor cells adhesion to extracellular matrix (ECM) proteins is the first step to the tumor metastasis. MMPs degrade the ECM to promote tumor metastasis. The aim of this study is to investigate the effects of small interfering RNA (siRNA) against CD147 (si-CD147) on hepatocellular carcinoma cells' (SMMC-7721) architecture and functions. Methods Flow cytometry and western blot assays were employed to detect the transfection efficiency of si-CD147. Confocal microscopy was used to determine the effects of si-CD147 on SMMC-7721 cells' cytoskeleton. Invasion assay, gelatin zymography and cell adhesion assay were employed to investigate the effects of si-CD147 on SMMC-7721 cells' invasion, gelatinase production and cell adhesive abilities. Western blot assay was utilized to detect the effects of si-CD147 on focal adhesion kinase (FAK), vinculiln and mitogen-activated protein kinase (MAPK) expression in SMMC-7721 cells. Results Downregulation of CD147 gene induced the alteration of SMMC-7721 cell cytoskeleton including actin, microtubule and vimentin filaments, and inhibited gelatinase production and expression, cells invasion, FAK and vinculin expression. si-CD147 also blocked SMMC-7721 cells adhesion to collagen IV and phosphorylation level of SAPK/JNKs. SAPK/JNKs inhibitor SP600125 inhibited gelatinase production and expression. Conclusion CD147 is required for normal tumor cell architecture and cell invasion. Downregulation of CD147 affects HCC cell structure and function. Moreover, the alteration of cell behavior may be related to SAPK/JNK Pathway. siRNA against CD147 may be a possible new approach for HCC gene therapy.

Osteoporosis is the most prevalent metabolic bone disease, especially when aggravated by aging and long-term bed rest of various causes and also when coupled with astronauts' longer missions in space. Research on the use of static magnetic fields (SMFs) has been progressing as a noninvasive method for osteoporosis due to the complexity of the disease, the inconsistency of the effects of SMFs, and the ambiguity of the mechanism. This paper studied the effects of mice subjected to hindlimb unloading (UL, HLU) and reloading by the 0.2 T–0.4 T static magnetic field (MMF). Primary bone marrow mesenchymal stem cells (BMSCs) were extracted to explore the mechanism. Eight-week-old male C57BL/6 mice were used as an osteoporosis model by HLU for four weeks. The HLU recovery period (reloading, RL) was carried out on all FVEs and recovered in the geomagnetic field (45–64 μT, GMF) and MMF, respectively, for 12 h/d for another 4 weeks. The tibia and femur of mice were taken; also, the primary BMSCs were extracted. MMF promoted the recovery of mechanical properties after HLU, increased the number of osteoblasts, and decreased the number of adipocytes in the bone marrow. MMF decreased the total iron content and promoted the total calcium content in the tibia. In vitro experiments showed that MMF promoted the osteogenic differentiation of BMSCs and inhibited adipogenic differentiation, which is related to iron metabolism, the Wnt/β-catenin pathway, and the PPARγ pathway. MMF accelerated the improvement in bone metabolism and iron metabolism in RL mice to a certain extent, which improved the bone quality of mice. MMF mainly promoted osteogenic differentiation and reduced the adipogenic differentiation of BMSCs, which provides a reliable research direction and transformation basis for the osteoporosis of elderly, bedridden patients and astronauts. [ABSTRACT FROM AUTHOR]

Pig manure, as an organic fertilizer, can significantly affect soil nutrient content, pH, and electrical conductivity. Moreover, the accumulation of heavy metals in pig manure and their potential ecological risks are also important concerns in soil management. Additionally, grazing systems may influence soil health and ecological balance by altering the soil microbial community structure. Therefore, this study investigates the impact of grazing Tibetan pigs on soil quality, focusing on the physicochemical properties, heavy metal accumulation, and microbial diversity. In the surface soil after grazing (GS0), pH, EC, AP, and AK were significantly higher than before grazing (NS0) (p < 0.05), while AN showed no significant difference. In the 10 cm soil layer, pH, EC, AK, and AN in GS10 were significantly higher than in NS10 (p < 0.05), whereas AP was significantly lower (p < 0.05). At the 20 cm depth, pH, EC, AP, and AK in GS20 were significantly higher than in NS20 (p < 0.05), but AN was significantly lower (p < 0.05). Overall, AN, AP, and AK decreased with increasing soil depth, while pH and EC showed no significant changes between the 10 cm and 20 cm layers (p > 0.05). In GS0 soil, the contents of Cd(II) and Zn(II) were significantly lower than those in NS0 (p < 0.05), while Pb(II) content was significantly higher (p < 0.05). There were no significant differences in Cu(II), Ni(II), Cr(VI), As(V), and Hg(II) (p > 0.05). In GS10 soil, Ni and Pb(II) contents were higher, whereas Cu(II), Zn(II), and Hg(II) contents were lower. In GS20 soil, Pb(II) and Cr(VI) contents were higher, while Cu(II) and Zn(II) contents were lower. Overall, GS had consistently lower Cd(II), Cu(II), Zn(II), and Hg(II) contents at all depths compared to NS, while Pb(II) and Cr(VI) contents were higher, showing depth-related variation trends, possibly due to plant absorption and heavy metal leaching. Probiotics such as Firmicutes, Bacteroidetes, and Acinetobacter increased significantly in soil, resulting in changes in the soil bacterial community. [ABSTRACT FROM AUTHOR]