High-velocity small-sized space debris with a diameter of 1–10 cm can cause huge damage to orbiting satellites and spacecraft. In recent years, the technology of actively removing small-sized space ...debris by high-energy pulsed laser irradiation has attracted widespread attention from scholars around the world, who strive for giving the maximum protection to the safety of the low-earth orbit environment. This paper focuses on exploring the dynamic behavior of centimeter-sized space debris under space-based pulsed laser irradiation. For this purpose, a fluid-structure-thermal-plasma multiphysics coupling model is built for space debris, and the effect law of plasma plumes produced by space debris after laser irradiation at different time is drawn. The simulation and measurement results are compared for analysis, verifying the validity and reliability of the proposed method and the built simulation model. The findings of this study are expected to provide an important theoretical reference and guidance for the research on the application of pulsed lasers to the active removal of centimeter-sized space debris.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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•Lithofacies decipher information about paleoclimate, hydrodynamic condition, and diagenesis.•Sedimentary environments and rate are the most important factors that influencing organic ...matter enrichment.•Macropores provided by intergranular pores between recrystallized calcite and microfractures.•Laminated organic-rich calcareous mudstone is the most promising shale oil lithofacies.
Recent economic production of shale oil in the lacustrine basin has prompted the reevaluation of fine-grained sedimentary rocks (FGSRs) in the Dongpu Sag, Bohai Bay Basin. In this study, FGSRs in the Eocene Shahejie Formation were examined using petrological, geochemical, and quantitative pore size characterization analyses to clarify lithofacies classification, sedimentary environment, controls of reservoir quality, and shale oil potential. The classification of lithofacies was based on total organic carbon content, sedimentary structure, and mineral content. The laminae formation processes and distribution indicate that the FGSRs were deposited in semi-deep to deep anoxic lacustrine environments with humid to semiarid climates. Laminated and layered FGSRs primarily comprise macropores and mesopores, accounting for an average of 68.02% and 27.33%, respectively, whereas micropores account for 4.65%. The macropores show a positive relationship with the carbonate mineral content and primarily comprise interparticle pores between recrystallized calcite and parallel interlayer microfractures. The mesopores are controlled by the content of clay and quartz-feldspathic minerals, revealing that they are primarily interparticle pores between rigid and soft grains. Micropores are dominated by crystalline pores in clay mineral. A low sedimentation rate is available for organic matter (OM) enrichment. The lithofacies containing recrystallized calcite laminae are high-quality shale oil reservoirs. The OM abundance, hydrocarbon generation potential, reservoir quality, and brittleness collectively highlight that OM-rich and moderately laminated calcareous mudstone and calcareous fine-grained mixed sedimentary rocks should be the focus of shale oil exploration. The results have important implications for shale oil development of the similar saline lacustrine basin worldwide.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A three-dimensional progressive damage model was developed in ANSYS to predict the damage accumulation of single bolted joint in composite laminates under in-plane tensile loading. First, we describe ...the formulation and algorithm of this model. Second, we calculate the failure loads of the joint in fibre reinforced epoxy laminated composite plates and compare it with the experiment results, which validates that our model can appropriately simulate the ultimate tensile strength of the joints and the whole process of failure of structure. Finally, this model is applied to study the failure process of the light-weight composite material (USN125). The study also has a great potential to provide a strong basis for bolted joints design in composite Laminates as well as a simple tool for comparing different laminate geometries and bolt arrangements.
The fore-angle and the lateral-rotation angle of PDC core bits, which are two main geometric parameters, have an important influence on the cutting efficiency and performance. Previous studies ...determined the ranges of two angles mainly depending on the effect of broken rock rather than its mechanical strength to examine the issue. Based on the strength factors, the paper uses finite element program ANSYS to optimize the fore-angle and the lateral-rotation angle of PDC cutters. The main geometric parameters are optimized and the optimal values are obtained under different circumstances, which provides a theoretical basis for reasonable design of the PDC core bits.
Mesenchymal stem cells-derived exosomes (MSC-Exo) are considered to have great potential in the treatment of human diseases. However, the role of MSC-Exo in the process of diabetes with sepsis and ...the underlying molecular mechanism remain unclear. Human pulmonary microvascular endothelial cells (HPMECs) were treated with high glucose (HG) and lipopolysaccharide (LPS). Cell viability, migration, angiogenesis were analyzed by cell counting kit 8 assay, transwell assay and tube formation assay. Transmembrane electrical resistance (TER) detection and FITC-dextran assay were performed to evaluate cell barrier function. The protein levels of cell permeability-related markers, ferroptosis-related markers, exosomes-related markers, Nrf2 and HO-1 were examined using western bolt (WB) analysis. Besides, the levels of inflammation factors were tested by ELISA, and the levels of ferroptosis-related indicators were examined using corresponding assay kits. Flow cytometry was employed to analyze stem cell markers. The identification of MSC-Exo was performed using transmission electron microscopy, nanoparticle tracking analysis and WB analysis. DIO staining was used to examine the uptake of MSC-Exo by HPMECs. HG treatment suppressed HPMECs viability, migration, angiogenesis and TER, while promoted permeability, inflammation and ferroptosis. LPS treatment aggravated HG-induced HPMECs dysfunction, inflammation and ferroptosis. After HPMECs were co-cultured with MSC-Exo, cell injury induced by HG + LPS could be relieved. Moreover, MSC-Exo treatment enhanced the activity of Nrf2/HO-1 pathway in HG + LPS-induced HPMECs, and Nrf2-silenced MSC-Exo could promote HG + LPS-induced HPMECs injury. MSC-Exo alleviated HG + LPS-induced HPMECs injury via activating Nrf2/HO-1 pathway, confirming that it might be used for the treatment of diabetes with sepsis.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Bone morphogenetic protein-4 (BMP4) is a key regulator of epithelial-mesenchymal transition (EMT), which is crucial for cancer cells to acquire chemoresistance. The effects of BMP4 on OXA sensitivity ...in HCC need to be elucidated.
Functional analysis of BMP4 on EMT-regulated OXA sensitivity was performed in human HCC specimens, in the HCC cell lines HepG2 and HCCLM3, and in a subcutaneous tumor model receiving OXA treatment. The downstream signaling targets of BMP4 in HCC were profiled and confirmed.
BMP4 expression was significantly increased in HCC tissue, and was correlated with tumor de-differentiation and unfavorable prognosis. BMP4 promoted HCC EMT and was correlated with OXA resistance. Blocking of BMP4 reversed EMT and increased OXA chemosensitivity in vitro and in vivo. ELK1, a transcription factor involved in EMT, was an important mediator of BMP4-induced OXA resistance in HCC. Blocking of MEK/ERK/ELK1 attenuated BMP4-induced EMT and enhanced OXA sensitivity.
BMP4 induces EMT and OXA chemoresistance via MEK/ERK/ELK1 signaling pathway in HCC. BMP4 may be a valuable therapeutic target for HCC patients receiving OXA-based chemotherapy.
•Research of BMP4 on EMT-regulated OXA sensitivity was performed in HCC specimens, cell lines and a nude mouse model.•BMP4 expression was significantly increased in HCC tissue, and was correlated with unfavorable prognosis of HCC patients.•BMP4 induces EMT and OXA chemoresistance via MEK/ERK/ELK1 signaling pathway in HCC.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Biofilms formed by spoilage and pathogenic bacteria increase microbial persistence, causing an adverse influence on the quality of seafood. The mono-species biofilms are widely reported, however, the ...contamination of multi-species biofilms and their matrix in food environments are still not fully understood. Here, we assessed the contamination of multi-species biofilms in three seafood processing environments with different hygiene levels by detecting bacterial number and three biofilm matrix components (carbohydrates, extracellular DNA (eDNA), and proteins). Samples comprising seven food matrix surfaces and eight food processing equipment surfaces were collected from two seafood processing plants (XY and XC) and one seafood market (CC). The results showed that the bacterial counts ranged from 1.89 to 4.91 CFU/cm2 and 5.68 to 9.15 BCE/cm2 in these surfaces by cultivation and real-time PCR, respectively. Six biofilm hotspots were identified, including four in CC and two in XY. Among the three processing environments, the amplicon sequence variants (ASVs) of Proteobacteria, Bacteroidetes, and Actinobacteria decreased with improved processing hygiene, while Firmicutes showed a decrease in the four most abundant phyla. The most prevalent bacteria belonged to genera Psychrobacter, Acinetobacter, and Pseudomonas, demonstrating the significant differences and alteration in bacterial community composition during different environments. From the biofilm hotspots, 15 isolates with strong biofilm forming ability were identified, including 7 Pseudomonas, 7 Acinetobacter, and 1 Psychrobacter. The Pseudomonas isolates exhibited the highest production of EPS components and three strong motilities, whose characteristics were positively correlated. Thus, this study verified the presence of multi-species biofilms in seafood processing environments, offering preliminary insights into the diversity of microbial communities during processing. It highlights potential contamination sources and emphasizes the importance of understanding biofilms composition to control biofilms formation in seafood processing environments.
Samples were taken from 3 seafood processing environments with different hygiene levels, and 16S rRNA amplicon sequencing and EPS components analysis were performed on the samples. 15 strains of strong biofilm forming bacteria were isolated, and their motilities and EPS secretion abilities were measured. This figure was created with BioRender.com. Display omitted
•Proteobacteria and Firmicutes were dominant in all processing environments.•ASV number of top 4 phyla was significantly correlated with hygiene level.•Acinetobacter and Pseudomonas promoted the formation of biofilm hotspots.•Motility ability was positively correlated with EPS production.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Intensive hydrothermal activity occurred during the deposition of the Lucaogou Formation.•The enrichment of both Sr and Li in the shales is consistent with a hydrothermal ...origin.•Hydrothermal activity supplied nutrients that enhanced paleoproductivity.
Organic matter enrichment in black shales has frequently been linked with hydrothermal activity. However, it is poorly understood how hydrothermal activity affected paleo-environments and the enrichment of organic matter in ancient lacustrine sediments. The hydrothermal activity recorded in the Middle Permian Lucaogou Formation (LCGF) in the Jimusar Sag, Junggar Basin, Northwest China, provides an ideal sedimentary archive to explore this issue. The mineralogical composition, major and trace element, total organic carbon, and sulfur content of forty-three shale samples of the LCGF were investigated to better understand how hydrothermal activity influences organic matter enrichment in lacustrine shales. The terrigenous influx, redox conditions, paleoproductivity, hydrothermal effects, and organic matter enrichment mechanisms are discussed. The results show that the terrigenous influx is insufficient overall, and the lower section of the LCGF has less detrital materials than the upper section. The redox conditions of the bottom water of the lake in the Jimusar Sag during deposition of the LCGF were suboxic to anoxic, which, combined with relatively high paleoproductivity, is favorable for organic matter enrichment. Hydrothermal activity occurred more frequently during deposition of the lower section compared with the upper section of LCGF. Hydrothermal fluids provided sufficient nutrients to enhance organic matter production during deposition of the LCGF and resulted in organic matter enrichment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•A novel design strategy to fine tune the Stokes shift of CDs is presented.•CDs with incredible huge Stokes shift of 161 nm were successfully synthesized.•The huge Stokes shift endows CDs with ...superior performance for highly contrast in vivo imaging.
In vivo imaging has become a key tool in biomedical studies because it provides a large amount of information about biological stimuli. Owing to the excellent biocompatibility and optical properties, carbon dots (CDs) have been widely used for fluorescence bioimaging. Whereas strong background autofluorescence from tissues is one of the largest concerns with CDs-based in vivo imaging, the development of CDs with large Stokes shifts is becoming critical for reducing the background autofluorescence. Herein, a novel design strategy to increase the Stokes shift of CDs was developed. By breaking the symmetry of the electronic structure of the precursor, the Stokes shift was significantly increased from 75 nm in p-phenylenediamine-derived CDs to 161 nm in 2-nitro-4-aminodiphenylamine (NAP)-derived CDs. In addition, the asymmetric electronic structure also enhanced the intramolecular charge transfer effect, which endowed NAP-CDs with a sensitive response to micro-environment polarity. As cancer cells possess lower polarity than normal cells, NAP-CDs would be effectively applied for cancer imaging with remarkably reduced background fluorescence from cell, tissue, organ to in vivo levels. The asymmetric electronic structure strategy reported here provides an important theoretical basis for the rational design and effective synthesis of CDs with large Stokes shift for practical biomedical applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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