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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]

Novel porous Co3O4 nanosheets (NSs) were synthesized on the flexible carbon cloth (CC) substrate by a facile hydrothermal method and applied to construct a non-enzymatic sensor for glucose detection. The sensor is based on the electro-catalytic oxidation of glucose on the surface of Co3O4 NSs. Since this particular nanostructure can provide large surface area and more active sites, the Co3O4 NSs non-enzymatic sensor exhibits excellent analytical performance, such as a high sensitivity (8506 μA mM−1 cm−2), a fast response time (less than 6 s), low detection limit of 1 μM, good selectivity, and long-term stability. The results suggest that the porous Co3O4 NSs have great potential applications in the development of sensors for enzyme-free detection of glucose. [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]

Astragalus membranaceus and Curcuma zedoaria, two traditional Chinese medicines, are widely used together in colorectal cancer adjuvant treatment. Many different mechanisms should be involved in the benefit effect of Astragalus membranaceus and Curcuma zedoaria. In this study, we established that the combined extract from Astragalus membranaceus and Curcuma zedoaria (HQEZ) decreased the metastasis ability in colorectal cancer cells (HCT116, a cell line of colorectal carcinoma established from Homo sapiens) in vitro, and the treatment induced the downregulation of EMT signal and decreased CXCR4 expression and the level of β-catenin. Overexpression of CXCR4 and the administration of the agonist and inhibitor to β-catenin signal pathway were used to explore the mechanism of Astragalus membranaceus and Curcuma zedoaria in colorectal cancer treatment. The data demonstrated that HQEZ increased the phosphorylation of β-catenin which related to the degradation of β-catenin, and it induced the downregulation of EMT signal and CXCR4. It meant that the influence of β-catenin should be a key event in the antimetastasis effects of Astragalus membranaceus-Curcuma zedoaria in colorectal cancer model. These findings revealed the potential effect and mechanism of Astragalus membranaceus-Curcuma zedoaria in colorectal cancer treatment and provided insight for optimization of the usage. [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]

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]

Background: Many of genome features which could help unravel the often complex post-speciation evolution of closely related species are obscured because of their location in chromosomal regions difficult to accurately characterize using standard genome analysis methods, including centromeres and repeat regions. Results: Here, we analyze the genome evolution and diversification of two recently diverged sister cotton species based on nanopore long-read sequence assemblies and Hi-C 3D genome data. Although D genomes are conserved in gene content, they have diversified in gene order, gene structure, gene family diversification, 3D chromatin structure, long-range regulation, and stress-related traits. Inversions predominate among D genome rearrangements. Our results support roles for 5mC and 6mA in gene activation, and 3D chromatin analysis showed that diversification in proximal-vs-distal regulatory-region interactions shape the regulation of defense-related-gene expression. Using a newly developed method, we accurately positioned cotton centromeres and found that these regions have undergone obviously more rapid evolution relative to chromosome arms. We also discovered a cotton-specific LTR class that clarifies evolutionary trajectories among diverse cotton species and identified genetic networks underlying the Verticillium tolerance of Gossypium thurberi (e.g., SA signaling) and salt-stress tolerance of Gossypium davidsonii (e.g., ethylene biosynthesis). Finally, overexpression of G. thurberi genes in upland cotton demonstrated how wild cottons can be exploited for crop improvement. Conclusions: Our study substantially deepens understanding about how centromeres have developed and evolutionarily impacted the divergence among closely related cotton species and reveals genes and 3D genome structures which can guide basic investigations and applied efforts to improve crops. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cell (MSC)-based cell therapy is a promising avenue for osteoarthritis (OA) treatment. In the present study, we evaluated the efficacy of intra-articular injections of culture-expanded allogenic adipose tissue-derived stem cells (ADSCs) for the treatment of anterior cruciate ligament transection (ACLT) induced rat OA model. The paracrine effects of major histocompatibility complex (MHC)-unmatched ADSCs on chondrocytes were investigated in vitro. Rats were divided into an OA group that underwent ACLT surgery and a sham-operated group that did not undergo ACLT surgery. Four weeks after surgery mild OA was induced in the OA group. Subsequently, the OA rats were randomly divided into ADSC and control groups. A single dose of 1 × 106 ADSCs suspended in 60 μL phosphate-buffered saline (PBS) was intra-articularly injected into the rats of the ADSC group. The control group received only 60 μL PBS. OA progression was evaluated macroscopically and histologically at 8 and 12 weeks after surgery. ADSC treatment did not cause any adverse local or systemic reactions. The degeneration of articular cartilage was significantly weaker in the ADSC group compared to that in the control group at both 8 and 12 weeks. Chondrocytes were co-cultured with MHC-unmatched ADSCs in trans-wells to assess the paracrine effects of ADSCs on chondrocytes. Co-culture with ADSCs counteracted the IL-1β-induced mRNA upregulation of the extracellular matrix-degrading enzymes MMP-3 and MMP-13 and the pro-inflammatory cytokines TNF-α and IL-6 in chondrocytes. Importantly, ADSCs increased the expression of the anti-inflammatory cytokine IL-10 in chondrocytes. The results of this study indicated that the intra-articular injection of culture-expanded allogenic ADSCs attenuated cartilage degeneration in an experimental rat OA model without inducing any adverse reactions. MHC-unmatched ADSCs protected chondrocytes from inflammatory factor-induced damage. The paracrine effects of ADSCs on OA chondrocytes are at least part of the mechanism by which ADSCs exert their therapeutic activity. [ABSTRACT FROM AUTHOR]

The Ti 3 SiC 2 and Ti 3 SiC 2 /Pb composites were tested under dry sliding conditions against Ni-based alloys (Inconel 718) at elevated temperatures up to 800 °C using a pin-on-disk tribometer. Detailed tribo-chemical changes of Pb on sliding surface were discussed. It was found that the tribological behavior were insensitive to the temperature from 25 °C (RT) to 600 °C (friction coefficient ≈0.61–0.72, wear rate ≈10 −3 mm 3 N m −1 ). An amount of Pb in the composites played a key role in lubricating with the temperature below 800 °C. The friction coefficient (≈0.22) and wear rate (≈10 −7 mm 3 N m −1 ) at elevated temperatures were both decreased by the added PbO. The wear mechanisms of Ti 3 SiC 2 /Pb-Inconel 718 tribo-pair at elevated temperatures were believed to be the combined effect of abrasive wear and tribo-oxidation wear. During the sliding, two oxidization reactions proceed, 2Pb+O 2 =2PbO (below 600 °C) and 6PbO+O 2 =2Pb 3 O 4 (800 °C). The friction coefficient and wear rate of the composites were reduced due to the self-lubricating effect of the tribo-oxidation products. [ABSTRACT FROM AUTHOR]

Salinity is a major limiting factor for agricultural production worldwide. A better understanding of the mechanisms of salinity stress response will aid efforts to improve plant salt tolerance. In this study, a combination of small RNA and mRNA degradome sequencing was used to identify salinity responsive-miRNAs and their targets in barley. A total of 152 miRNAs belonging to 126 families were identified, of which 44 were found to be salinity responsive with 30 up-regulated and 25 down-regulated respectively. The majority of the salinity-responsive miRNAs were up-regulated at the 8h time point, while down-regulated at the 3h and 27h time points. The targets of these miRNAs were further detected by degradome sequencing coupled with bioinformatics prediction. Finally, qRT-PCR was used to validate the identified miRNA and their targets. Our study systematically investigated the expression profile of miRNA and their targets in barley during salinity stress phase, which can contribute to understanding how miRNAs respond to salinity stress in barley and other cereal crops. [ABSTRACT FROM AUTHOR]

Arachis monticola (2n = 4x = 40) is the only allotetraploid wild peanut within the Arachis genus and section, with an AABB-type genome of ∼2.7 Gb in size. The AA-type subgenome is derived from diploid wild peanut Arachis duranensis , and the BB-type subgenome is derived from diploid wild peanut Arachis ipaensis. A. monticola is regarded either as the direct progenitor of the cultivated peanut or as an introgressive derivative between the cultivated peanut and wild species. The large polyploidy genome structure and enormous nearly identical regions of the genome make the assembly of chromosomal pseudomolecules very challenging. Here we report the first reference quality assembly of the A. monticola genome, using a series of advanced technologies. The final whole genome of A. monticola is ∼2.62 Gb and has a contig N50 and scaffold N50 of 106.66 Kb and 124.92 Mb, respectively. The vast majority (91.83%) of the assembled sequence was anchored onto the 20 pseudo-chromosomes, and 96.07% of assemblies were accurately separated into AA- and BB- subgenomes. We demonstrated efficiency of the current state of the strategy for de novo assembly of the highly complex allotetraploid species, wild peanut (A. monticola), based on whole-genome shotgun sequencing, single molecule real-time sequencing, high-throughput chromosome conformation capture technology, and BioNano optical genome maps. These combined technologies produced reference-quality genome of the allotetraploid wild peanut, which is valuable for understanding the peanut domestication and evolution within the Arachis genus and among legume crops. [ABSTRACT FROM AUTHOR]