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Mitochondria play a crucial role in numerous biological processes; however, limited methods and research have focused on revealing mitochondrial heterogeneity at the single‐cell level. In this study, we optimized the DNBelab C4 single‐cell ATAC (assay for transposase‐accessible chromatin) sequencing workflow for single‐cell mitochondrial sequencing (C4_mtscATAC‐seq). We validated the effectiveness of our C4_mtscATAC‐seq protocol by sequencing the HEK‐293T cell line with two biological replicates, successfully capturing both mitochondrial content (~68% of total sequencing data) and open chromatin status simultaneously. Subsequently, we applied C4_mtscATAC‐seq to investigate two mouse tissues, spleen and bone marrow, obtained from two mice aged 2 months and two mice aged 23 months. Our findings revealed higher mitochondrial DNA (mtDNA) content in young tissues compared to more variable mitochondrial content in aged tissues, consistent with higher activity scores of nuclear genes associated with mitochondrial replication and transcription in young tissues. We detected a total of 22, 15, and 21 mtDNA mutations in the young spleen, aged spleen, and bone marrow, respectively, with most variant allele frequencies (VAF) below 1%. Moreover, we observed a higher number of mtDNA mutations with higher VAF in aged tissues compared to young tissues. Importantly, we identified three mtDNA variations (m.9821A>T, m.15219T>C, and m.15984C>T) with the highest VAF in both aged spleen and aged bone marrow. By comparing cells with and without these mtDNA variations, we analyzed differential open chromatin status to identify potential genes associated with these mtDNA variations, including transcription factors such as KLF15 and NRF1. Our study presents an alternative single‐cell mitochondrial sequencing method and provides crude insights into age‐related single‐cell mitochondrial variations. [ABSTRACT FROM AUTHOR]

The corrosion behaviors of Ti3SiC2/Cu composites synthesized by spark plasma sintering technique were investigated at 900°C in three molten salts including NaCl, Na2SO4, and Na2CO3, and the related corrosion mechanism was discussed. The morphology and composition of the composites after corrosion were characterized by scanning electron microscopy and X‐ray photoelectron spectroscopy. The results indicated that the weight gain per unit surface area of the composites was negative in molten Na2CO3, while it was positive and relatively small in molten NaCl and Na2SO4. The high weight loss of the composites in molten Na2CO3 was owing to that in molten Na2CO3, an oxidation layer of the composites was dissolved, and oxygen diffused through the layer to corrode the substrate inside. Thus, in the molten Na2CO3, the composites exhibited a worse corrosion resistance. However, in molten NaCl and Na2SO4, an oxidation layer containing SiO2 and TiO2 was formed on the surface of the composites, inhibiting its further corrosion. Conclusively, the composites showed better corrosion resistance in molten NaCl and Na2SO4. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel approach for sampling indirect illumination based on bidirectional path tracing and world space resampling reservoir. We cache light subpaths with high contribution in a world space grid, allowing for sampling at arbitrary vertices along the eye path. In order to find optimal samples, we continuously update the reservoirs stored in each cell according to the resampling principles. Experiments have shown that our algorithm achieves noticeable noise reduction in scenes lit by indirect light compared with path tracing, at the cost of additional time and memory consumption, while still maintaining interactive frame rates. In some special cases, our method even shows better results than a plain bidirectional path tracer, in terms of both image quality and performance. [Display omitted] • Path tracing (PT) has a poor performance at scenes lit mainly by indirect light. • Bidirectional path tracing (BDPT) is more efficient than PT but too resource-intensive. • World space resampling reservoir makes the sampling of light subpaths more efficient. • Our method achieves remarkable noise reduction compared with PT and BDPT. • Our method runs at an interactive frame rate. [ABSTRACT FROM AUTHOR]

Background: One of the most challenging aspects of colon cancer (CC) prognosis and treatment is liver-tropic metastasis. Astragalus mongholicus Bunge—Curcuma aromatica Salisb. (AC) is a typical medication combination for the therapy of many malignancies. Our previous studies found that AC intervention inhibits liver metastasis of colon cancer (LMCC). Nevertheless, the comprehensive anti-metastasis mechanisms of AC have not been uncovered. Methods: In bioinformatics analysis, RNA-seq data of CC and LMCC patients were collected from TCGA and GEO databases, and differentially expressed genes (DEGs) were identified. The biological processes and signaling pathways involved in DEGs were enriched by GO and KEGG. The protein–protein interaction (PPI) network of DEGs was established and visualized using the Cytocape software, followed by screening Hub genes in the PPI network using Degree value as the criterion. Subsequently, the expression and survival relevance of Hub gene in COAD patients were verified. In the experimental study, the effects of AC on the inhibition of colon cancer growth and liver metastasis were comprehensively evaluated by cellular and animal models. Finally, based on the results of bioinformatics analysis, the possible mechanisms of AC inhibition of colon cancer EMT and liver metastasis were explored by in vivo and in vitro pharmacological experiments. Results: In this study, we obtained 2386 DEGs relevant to LMCC from the COAD (colon adenocarcinoma) and GSE38174 datasets. Results of GO gene function and KEGG signaling pathway enrichment analysis suggested that cellular EMT (Epithelial-mesenchymal transition) biological processes, Cytokine-cytokine receptor interaction and PI3K/Akt signaling pathways might be closely related to LMCC mechanism. We then screened for CXCL8, the core hub gene with the highest centrality within the PPI network of DEGs, and discovered that CXCL8 expression was negatively correlated with the prognosis of COAD patients. In vitro and in vivo experimental evidence presented that AC significantly inhibited colon cancer cell proliferation, migration and invasion ability, and suppressed tumor growth and liver metastasis in colon cancer orthotopic transplantation mice models. Concomitantly, AC significantly reduced CXCL8 expression levels in cell supernatants and serum. Moreover, AC reduced the expression and transcription of genes related to the PI3K/AKT pathway while suppressing the EMT process in colon cancer cells and model mice. Conclusions: In summary, our research predicted the potential targets and pathways of LMCC, and experimentally demonstrated that AC might inhibit the growth and liver metastasis in colon cancer by regulating EMT via the CXCL8/CXCR2 axis and PI3K/AKT/mTOR signaling pathway, which may facilitate the discovery of mechanisms and new therapeutic strategies for LMCC. [ABSTRACT FROM AUTHOR]

Ti 3 SiC 2 /Cu composite, a new wide temperature range intelligent lubricating functional material, was fulfilled, for mechanical equipment components, by Spark Plasma Sintering process. The microstructure, composition and mechanical properties of the Ti 3 SiC 2 /Cu composites (TSC-Cu) were investigated. Additionally, the friction and wear behaviors of TSC-Cu sliding against Inconel 718 were conducted on a pin-on-disk configuration at a sliding speed of 0.5 m/s under a load of 5 N at 25–800 °C. For comparison, the tribological property of polycrystalline Ti 3 SiC 2 /Inconel 718 was measured in an identical condition. The worn surface of TSC-Cu was analyzed by SEM, EDS and XPS, respectively. The results indicated that TSC-Cu consisted of Ti 3 SiC 2 , TiC and Cu 3 Si. It was worth noting that the as-formed Cu 3 Si uniformly distributed along the grain boundary of Ti 3 SiC 2. As for mechanical property, the addition of Cu increased the hardness, compressive strength of TSC-Cu but lowered its flexural strength. Compared with polycrystalline Ti 3 SiC 2 , the average friction coefficient of TSC-Cu was higher at 25–400 °C whereas it was lower at 600 °C and 800 °C. The lower friction coefficient was owing to the cooperative lubricating characteristic of tribo-oxidation films containing TiO 2 , SiO 2 and CuO. Furthermore, the wear rate of TSC-Cu was absolutely lower than that of polycrystalline Ti 3 SiC 2 , which resulted from the effective surface strengthening effect of the as-formed hard TiC product. Moreover, the wear mechanism of the composite changed from three-body abrasion wear to adhesion wear and tribo-oxidation wear, with the temperature increasing from RT to 800 °C. [ABSTRACT FROM AUTHOR]

In this paper, we establish a triple-coincidence positron annihilation lifetime (PAL) spectrometer based on fast–fast coincidence. It can be used to accurately characterize atomic-scale defects in radioactive samples. The PAL spectrometer consists of three BaF 2 detectors and a fast–fast coincidence system, which is composed of analogic electronic modules. The timing resolution of the spectrometer is approximately 198 ps, and the coincidence counting rate can reach 44 s−1 for a 0.9 MBq 22Na source. The results demonstrate that with 22Na activity at 0.9 MBq, the triple-coincidence PAL spectrometer can operate with high precision at 60Co activity levels of up to 4.3 MBq. However, when the activity of 60Co exceeds this threshold, the lifetime spectrum experiences noticeable distortion and an increasing background. As a result, the reliability of the measurement results is compromised. Despite this limitation, the spectrometer was proved successful in characterizing defects in neutron-irradiated RPV steels. [ABSTRACT FROM AUTHOR]

The electrochemical corrosion behaviors of Ti3SiC2/Cu composite and polycrystalline Ti3SiC2 in a 3.5% NaCl medium were investigated by dynamic potential polarization, potentiostat polarization, and electrochemical impedance spectroscopy. The polycrystalline Ti3SiC2 was tested on the identical condition as a control. The characterizations of XRD, X‐ray photoelectron spectroscopy, scanning electron microscope, and energy‐dispersive spectrometer were used to study the relevant passivation behavior and corrosive mechanism. The self‐corrosion current density of Ti3SiC2/Cu (6.46 × 10−6 A/cm2) was slightly higher than that of Ti3SiC2 (1.64 × 10−7 A/cm2). Under open circuit potential, the corrosion resistance of Ti3SiC2/Cu was better than that of Ti3SiC2. Ti3SiC2/Cu exhibited a typical passivation feature with a narrow passivation interval and a breakdown phenomenon. The better corrosion resistance of Ti3SiC2 was due to the more stable Si layer of the former. In comparison, for Ti3SiC2/Cu composites, Cu reacted with the reactive Si layers in Ti3SiC2 to form Cu–Si compounds and TiC, destroying the weak interaction between Si layers and Ti–C layers. In the other hand, the as‐formed Cu–Si compounds and TiC dissolved during the corrosion of Ti3SiC2/Cu in the 3.5% NaCl medium, causing to the destruction of the passivation film on its surface. [ABSTRACT FROM AUTHOR]

Method of soft metal (Cu) strengthening of Ti3SiC2 was conducted to increase the hardness and improve the wear resistance of Ti3SiC2. Ti3SiC2/Cu composites containing 15 vol.% Cu were fabricated by Spark Plasma Sintering (SPS) in a vacuum. The effect of the sintering temperature on the phase composition, microstructure and mechanical properties of the composites was investigated in detail. The as-synthesized composites were thoroughly characterized by scanning electron micrography (SEM), optical micrography (OM) and X-ray diffractometry (XRD), respectively. The results indicated that the constituent of the Ti3SiC2/Cu composites sintered at different temperatures included Ti3SiC2, Cu3Si and TiC. The formation of Cu3Si and TiC originated from the reaction between Ti3SiC2 and Cu, which was induced by the presence of Cu and the de-intercalation of Si atoms Ti3SiC2. OM analysis showed that with the increase in the sintering temperature, the reaction between Ti3SiC2 and Cu was severe, leading to the Ti3SiC2 getting smaller and smaller. SEM measurements illustrated that the uniformity of the microstructure distribution of the composites was restricted by the agglomeration of Cu, controlling the mechanical behaviors of the composites. At 1000 °C, the distribution of Cu in the composites was relatively even; thus, the composites exhibited the highest density, relatively high hardness and compressive strength. The relationships of the temperature, the current and the axial dimension with the time during the sintering process were further discussed. Additionally, a schematic illustration was proposed to explain the related sintering characteristic of the composites sintered by SPS. The as-synthesized Ti3SiC2/Cu composites were expected to improve the wear resistance of polycrystalline Ti3SiC2. [ABSTRACT FROM AUTHOR]

The corrosion behaviors of Ti 3 SiC 2 /Cu composites in dilute HNO 3 (11.6%) and concentrated H 2 SO 4 were investigated by the soaking method. The morphology, composition and elemental content of the composites before and after corrosion were analyzed to determine the corrosion products and the corresponding corrosion mechanism. The results found that the mass losses of the Ti 3 SiC 2 /Cu composites after soaking in the dilute HNO 3 and concentrated H 2 SO 4 for 50 days were 148.58 mg/cm2 and -2.90 mg/cm2, respectively, which indicated that the corrosion resistance of Ti 3 SiC 2 /Cu composites in concentrated H 2 SO 4 was superior than that in dilute HNO 3. It was deduced that in dilute HNO 3 , Cu in the Ti 3 SiC 2 /Cu composites reacted with dilute HNO 3 and dissolved in it, and Ti and Si in the Ti 3 SiC 2 /Cu composites reconstructed to form Ti 5 Si 3. The better corrosion resistance of Ti 3 SiC 2 /Cu composites in concentrated H 2 SO 4 was owing to a passivation film consisting of TiO 2 and SiO 2. Moreover, the appearance of the formation of CuO in the initial corrosion further strengthened its corrosion resistance in concentrated H 2 SO 4. [ABSTRACT FROM AUTHOR]

In this work, we studied the evolution of vacancy-like defects and the formation of brittle precipitates in a reduced-activation V−Cr−Mn medium-entropy alloy. The evolution of local electronic circumstances around Cr and Mn enrichments, the vacancy defects, and the CrMn3 precipitates were characterized by using scanning electron microscopy with energy-dispersive spectroscopy, X-ray diffraction, and positron annihilation spectroscopy. The microstructure measurements showed that the Mn and Cr enrichments in the as-cast sample significantly evolved with temperature, i.e., from 400 °C, the Cr/Mn-segregated regions gradually dissolved into the matrix and then disappeared, and from 900 °C to 1000 °C, they existed as CrMn3 precipitates. The crystallite size of the phase corresponding to CrMn3 precipitates was about 29.4 nm at 900 °C and 43.7 nm at 1000 °C. The positron annihilation lifetime results demonstrated that the vacancies mediated the migration of Cr and Mn, and Cr and Mn segregation finally led to the formation of CrMn3 precipitates. The coincidence Doppler broadening results showed that the characteristic peak moved to the low-momentum direction, due to an increase in the size of the vacancy defects at the interface and the formation of CrMn3 precipitates. [ABSTRACT FROM AUTHOR]

Objective: Young adult patients with cancer are a growing concern. By means of network analysis, this study aimed to explore the interplay between dignity-related distress and quality of life (QoL) in young adult patients with cancer when they undergo active treatments.Methods: In this cross-sectional study, 309 young adults aged 18-39 and diagnosed with malignant tumors were recruited from an oncology center in China between September 2020 and August 2021. Participants completed the Patient Dignity Inventory and SF-36 questionnaires. Network analysis was applied to examine the network structure.Results: Overall, the core facets of dignity-related distress were negatively related to QoL and its corresponding domains, either directly or indirectly. Developmental distress played a central role among estimated networks and strongly interplayed with most QoL domains, especially the mental domains. Symptom distress was the only facet consistently interplayed with the physical domains of QoL (i.e., physical function and bodily pain). The social aspects were also revealed in the association between limited social support and vitality.Conclusions: Early attention must be paid to guarantee the need of preserving dignity and enhancing QoL for young adult patients. [ABSTRACT FROM AUTHOR]

Ti3SiC2-PbO-Ag composites (TSC-PA) were successfully prepared using the spark plasma sintering (SPS) technique. The ingredient and morphology of the as-synthesized composites were elaborately investigated. The tribological properties of the TSC-PA pin sliding against Inconel 718 alloys disk at room temperature (RT) to 800 °C were examined in air. The wear mechanisms were argued elaborately. The results showed that the TSC-PA was mainly composed of Ti3SiC2, Pb, and Ag. The average friction coefficient of TSC-PA gradually decreased from 0.72 (RT) to 0.3 (800 °C), with the temperature increasing from RT to 800 °C. The wear rate of TSC-PA showed a decreasing trend, with the temperature rising from RT to 800 °C. The wear rate of Inconel 718 exhibited positive wear at RT and negative wear at elevated temperatures. The tribological property of TSC-PA was related to the tribo-chemistry, and the abrasive and adhesive wear. [ABSTRACT FROM AUTHOR]

Ti3SiC2/CaF2 composites were prepared by the spark plasma sintering (SPS) process. Both the microstructure of Ti3SiC2/CaF2 and the influence of test temperature on the tribological behavior of the Ti3SiC2/CaF2 composites were investigated. The synergistic effect of friction and oxidation was evaluated by analyzing the worn surface morphology. The results showed that Ti3SiC2/CaF2 were still brittle materials after adding CaF2, which was in agreement with Ti3SiC2. The hardness, relative density, flexural strength and compressive strength of the Ti3SiC2/CaF2 composites were slightly lower than those of Ti3SiC2, and the addition of CaF2 decreased the decomposition temperature of Ti3SiC2 from 1350 to 1300 °C. Simultaneously, as the temperature of the test increased, the friction coefficient of Ti3SiC2/CaF2 showed a downward trend (from 0.81 to 0.34), and its the wear rate was insensitive. [ABSTRACT FROM AUTHOR]

Objective We aimed to investigate the mechanisms underlying the effects of Huangqi and Ezhu combined with 5-fluorouracil (5-FU) in the treatment of colon cancer. Methods One male BALB/c mouse was used to generate the orthotopic tumor, and orthotopic tumor tissue was transplanted into 80 male BALB/c mice to establish the CT26. WT mouse model. These 80 mice were randomly divided into (i) the model group, (ii) the 5-FU group (25 mg/kg), (iii) the high-dose huangqi plus ezhu group (12 g/kg), (iv) the mid-dose huangqi plus ezhu group (6 g/kg), (v) the low-dose huangqi plus ezhu group (3 g/kg), (vi) the high-dose combination therapy group (12 g/kg + 25 mg/kg), (vii) the mid-dose combination therapy group (6 g/kg + 25 mg/kg), and (viii) the low-dose combination therapy group (3g/kg +25 mg/kg) (n = 10 mice per group). Treatment lasted for 3 weeks. The tumor inhibition rate was calculated by collecting tumors after the mice were killed. Chemokin (C-X-C) motif ligand 10 (CXCL10), Chemokin (C-X-C) motif receptor 3 (CXCR3), Chemokin (C-C) motif ligand 3 (CCL3), and Chemokin (C-C) motif receptor 5 (CCR5) mRNA and protein expression levels in tumor tissue, lymphoid tissue, and liver tissue were measured by RT-PCR and western blot, respectively. Results Compared with model group, the tumor inhibition rate in each treatment group was increased (P < 0.01). Compared with 5-FU group, the tumor inhibition rate of high-dose, mid-dose, low-dose huangqi plus ezhu, groups and high-dose, mid-dose, low-dose combination therapy group was decreased (P < 0. 01). Compared with the high-dose huangqi plus ezhu group, the tumor inhibition rate of high-dose combination therapy group was increased (P < 0. 01), and low-dose huangqi plus ezhu groups were decreased (P < 0. 01). Compared with mid-dose huangqi plus ezhu group, the tumor inhibition rate of low-dose huangqi plus ezhu group was decreased (P < 0. 01), and the mid-dose combination therapy group group was increased (P < 0. 01). Compared with the high-dose combination therapy group, the tumor inhibition rate of mid-dose combination therapy group was increased (P < 0. 01). Compared with mid-dose combination therapy group, the tumor inhibition rate of low-dose combination therapy group was decreased (P <0. 01). Compared with the low-dose combination therapy group, the tumor inhibition rate of low-dose huangqi plus ezhu group was decreased(P <0. 01). Compared with the model group, mRNA and protein levels of CXCL10, CXCR3, CCL3, and CCR5 were lower in each treatment group (P <0. 01). Compared with the 5-FU group, mRNA and protein levels of CXCL10, CXCR3, CCL3, and CCR5 were higher in the mid- and low-dose huangqi plus ezhu groups (P <0. 05, P <0. 01) and lower in the combination therapy groups (P <0. 01). Compared with the 5-FU group, the mRNA and protein levels of CCL3 in orthotopic tumor tissue, lymph node tissue, and liver tissue and the protein levels of CCR5 in the liver tissue of the high-dose huangqi plus ezhu group were increased (P <0. 01), and the mRNA levels of CXCL10 and CXCR3 in the high-dose huangqi plus ezhu group were increased (P <0. 05, P <0. 01). Compared with the high-dose huangqi plus ezhu group, mRNA and the protein levels of chemokines and receptors were decreased in the high-dose combination therapy group (P < 0. 05), the protein levels of chemokines and receptors in orthotopic tumor tissue and lymph node tissue were increased in the mid-dose and low-dose huangqi plus ezhu groups (P < 0. 05), the protein levels of CXCL10, CXCR3, and CCR5 in liver tissue were increased in the mid-dose and low-dose huangqi plus ezhu groups (P < 0. 05), the mRNA levels of chemokines and receptors were increased in the low-dose huangqi plus ezhu group(P <0. 05), and the mRNA levels of CXCR3, CCL3, and CCR5 were increased in the mid-dose huangqi plus ezhu group (P <0. 05). Compared with the mid-dose huangqi plus ezhu group, the mRNA and protein levels of chemokines and receptors were decreased in the mid-dose combination therapy group (P < 0. 05), the protein levels of chemokines and receptors in orthotopic tumor tissue were increased in the low-dose huangqi plus ezhu group (P < 0. 05), the protein levels of CXCL10 and CCL3 in lymph node tissue were increased (P < 0. 05), the protein levels of CXCL10 and CCR5 in liver tissue were increased (P <0. 05), and the mRNA levels of CXCL10 and CCL3 were increased in the low-dose huangqi plus ezhu group (P <0. 05). Compared with the high-dose combination therapy group, the mRNA and protein levels of chemokines and receptors were increased in the low-dose combination therapy group (P < 0. 05), the protein levels of CCL3 ad CXCL10 in orthotopic tumor tissue were increased in the mid-dose combination therapy group (P < 0. 05), the protein levels of CCR5, CXCL10, and CXCR3 in lymph node tissue were increased in the mid-dose combination therapy group(P <0. 05), the protein levels of CXCL10 and CXCR3 in liver tissue were increased in the mid-dose combination therapy group (P <0. 05), and the mRNA levels of CXCR3 were increased in the mid-dose combination therapy group (P <0. 05). Compared with the mid-dose combination therapy group, the protein levels of CXCL10, CXCR3, and CCR5 in orthotopic tumor tissue were increased in the low-dose combination therapy group (P <0. 05), the protein levels of CXCL10 and CXCR3 in lymph node tissue were increased in the low-dose combination therapy group (P <0. 05), the protein levels of CXCR3 and CCR5 in liver tissue were increased in the low-dose combination therapy group (P < 0. 05), and the mRNA levels of CXCR3 and CCL3 were increased in the low-dose combination therapy group (P <0.05). Compared with the low-dose combination therapy group, the mRNA and protein levels of chemokines and receptors were increased in the low-dose huangqi plus ezhu group (P < 0. 05). Conclusions The combination of Huangqi and Ezhu can inhibit the proliferation of CT26. WT orthotopic tumors, and combination therapy with 5-FU could further enhance the efficacy. The underlying therapeutic mechanism may be related to the downregulation of the CXCL10/CXCR3 and CCL3/CCR5 axes, which are closely related to tumor invasion and metastasis. [ABSTRACT FROM AUTHOR]