52 research outputs found

    Intelligence of Astronomical Optical Telescope: Present Status and Future Perspectives

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    Artificial intelligence technology has been widely used in astronomy, and new artificial intelligence technologies and application scenarios are constantly emerging. There have been a large number of papers reviewing the application of artificial intelligence technology in astronomy. However, relevant articles seldom mention telescope intelligence separately, and it is difficult to understand the current development status and research hotspots of telescope intelligence from these papers. This paper combines the development history of artificial intelligence technology and the difficulties of critical technologies of telescopes, comprehensively introduces the development and research hotspots of telescope intelligence, then conducts statistical analysis on various research directions of telescope intelligence and defines the research directions' merits. All kinds of research directions are evaluated, and the research trend of each telescope's intelligence is pointed out. Finally, according to the advantages of artificial intelligence technology and the development trend of telescopes, future research hotspots of telescope intelligence are given.Comment: 19 pages, 6 figure, for questions or comments, please email [email protected]

    Multilevel Nitrogen Additions Alter Chemical Composition and Turnover of the Labile Fraction Soil Organic Matter via Effects on Vegetation and Microorganisms

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    Global nitrogen (N) deposition greatly impacts soil carbon sequestration. A 2- yr multiple N addition (0, 10, 20, 40, 80, and 160 kg N·ha- 1·yr- 1) experiment was conducted in alpine grassland to illustrate the mechanisms underlying the observed soil organic matter (SOM) dynamics on the Qinghai- Tibet Plateau (QTP). Labile fraction SOM (LF- SOM) fingerprints were characterized by pyrolysis- gas chromatography/tandem- mass spectrometry, and microbial functional genes (GeoChip 4.6) were analyzed in conjunction with LF- SOM fingerprints to decipher the responses of LF- SOM transformation to N additions. The significant correlations between LF- SOM and microbial biomass, between organic compounds in LF- SOM and compound degradation- related genes, and between LF- SOM and net ecosystem exchange implied LF- SOM were the main fraction utilized by microorganisms and the most sensitive fraction to N additions. The LF- SOM increased at the lowest N addition levels (10 and 20 kg N·ha- 1·yr- 1) and decreased at higher N addition levels (40 to 160 kg N·ha- 1·yr- 1), but the decrease of LF- SOM was weakened at 160 kg N·ha- 1·yr- 1 addition. The nonlinear response of LF- SOM to N additions was due to the mass balance between plant inputs and microbial degradation. Plant- derived compounds in LF- SOM were more sensitive to N addition than microbial- derived and aromatic compounds. It is predicted that when the N deposition rate increased by 10 kg N·ha- 1·yr- 1 on the QTP, carbon sequestration in the labile fraction may increase by nearly 170% compared with that under the current N deposition rate. These findings provide insight into future N deposition impacts on LF- SOM preservation on the QTP.Key PointsThe LF- SOM quantity increased at the lowest N additions (N10 and N20) and decreased from N40 to N160, but the decrease was weakened at the highest N addition (N160)Plant- derived compounds in LF- SOM were more sensitive to N addition than microbial- derived and aromatic compoundsThe organic compounds in LF- SOM were significantly correlated with compound degradation- related genesPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154963/1/jgrg21637_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154963/2/jgrg21637.pd

    COVID-19 vaccination and the risk of autoimmune diseases: a Mendelian randomization study

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    BackgroundIn recent times, reports have emerged suggesting that a variety of autoimmune disorders may arise after the coronavirus disease 2019 (COVID-19) vaccination. However, causality and underlying mechanisms remain unclear.MethodsWe collected summary statistics of COVID-19 vaccination and 31 autoimmune diseases from genome-wide association studies (GWAS) as exposure and outcome, respectively. Random-effects inverse variance weighting (IVW), MR Egger, weighted median, simple mode, and weighted mode were used as analytical methods through Mendelian randomization (MR), and heterogeneity and sensitivity analysis were performed.ResultsWe selected 72 instrumental variables for exposure (p < 5 × 10−6; r2 < 0.001, genetic distance = 10,000 kb), and MR analyses showed that COVID-19 vaccination was causally associated with an increased risk of multiple sclerosis (MS) (IVW, OR: 1.53, 95% CI: 1.065–2.197, p = 0.026) and ulcerative colitis (UC) (IVW, OR: 1.00, 95% CI: 1.000–1.003, p = 0.039). If exposure was refined (p < 5 × 10−8; r2 < 0.001, genetic distance = 10,000 kb), the associations became negative. No causality was found for the remaining outcomes. These results were robust to sensitivity and heterogeneity analyses.ConclusionOur study provided potential evidence for the impact of COVID-19 vaccination on the risk of MS and UC occurrence, but it lacks sufficient robustness, which could provide a new idea for public health policy

    Long Noncoding RNA EGFR-AS1 Promotes Cell Proliferation by Increasing EGFR mRNA Stability in Gastric Cancer

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    Background/Aims: LncRNA EGFR-AS1 is an antisense transcript of EGFR, which plays a key role in gastric cancer progression. This study was aimed to explore the effects of lncRNA EGFR-AS1 on GC and the underling mechanisms. Methods: The silencing of EGFR-AS1 expression was performed by using EGFR-AS1 shRNA lentivirus in MGC803 and SGC-7901 GC cell. The levels of lncRNA EGFR-AS1 and EGFR were detected by qPCR and western blot. Cell proliferation was assessed by CCK-8, EdU, and colony formation assays. The EGFR mRNA stability was explored by using RNA synthesis inhibitor α-amanitin. Results: In our study, EGFR-AS1 significantly up-regulated in GC tissues and correlated with tumor size. And the expression of EGFR-AS1 positively correlated with EGFR in tissues. Moreover, knock-down of EGFR-AS1 inhibited the proliferation of GC cells via suppressing EGFR-dependent PI3K/AKT pathway in vitro and in vivo. Mechanismly, depletion of EGFR-AS1 was found to decrease EGFR expression by reduction of EGFR mRNA stability. Conclusion: Our findings suggested that EGFR-AS1 might have an oncogenic effect on GC and serve as a potential target of GC

    Tetra­kis-μ-l-alanine-κ8 O:O′-bis­[tetra­aqua­terbium(III)] hexa­perchlorate

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    The asymmetric unit of the title compound, [Tb2(C3H7NO2)4(H2O)8](ClO4)6, contains a dinuclear cation and six perchlorate anions, one of which is disordered. In the cation, the four l-alanine mol­ecules are present in their zwitterionic form and bridge two Tb3+ ions through their carboxyl­ate O atoms. Each Tb atom is also coordinated by four water mol­ecules in a square-anti­prismatic geometry. In the crystal structure, the cations and anions are held together via inter­molecular O—H⋯O and N—H⋯O hydrogen bonds

    Development of cordycepin formulations for preclinical and clinical studies

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    There is extensive literature on in vivo studies with cordycepin but these studies were generally conducted without validation of the various formulations, especially in terms of the solubility of cordycepin in the dosing vehicles used. Cordycepin is a promising drug candidate in multiple therapeutic areas and there is a growing interest in studies aimed at assessing the pharmacological activity of this compound in relevant animal disease models. It is likely that many reported in vivo studies used formulations in which cordycepin was incompletely soluble. This can potentially confound the interpretation of pharmacokinetics and efficacy results. Furthermore, the presence of particles in intravenously administered suspension can cause adverse effects and should be avoided. Here we present the results from our development of simple and readily applicable formulations of cordycepin based on quantitative solubility assessment. Homogeneous solutions of cordycepin were prepared in phosphate-buffered saline (PBS) at different pH levels, suitable as formulations for both intravenously and oral administration. For the purpose of high-dose oral administration we also developed propylene glycol (PPG)-based vehicles in which cordycepin is completely soluble. The stability of the newly developed formulations was also assessed, as well the feasibility of their sterilisation by filtration. Additionally, an HPLC-UV method for the determination of cordycepin in the formulations, which may also be useful for other purposes, was developed and validated. Our study could provide useful information for improvement of future preclinical and clinical studies involving cordycepin

    Expansion of Ovarian Cancer Stem-like Cells in Poly(ethylene glycol)-Cross-Linked Poly(methyl vinyl ether-alt-maleic acid) and Alginate Double-Network Hydrogels

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    A better understanding of cancer stem cells (CSCs) is essential for research on cancer therapy and drug resistance. Currently, increasingly more investigations are focused on obtaining CSCs to study the mechanism of their enhanced malignancy. In this work, three kinds of double-network hydrogels (PEMM/alginate), consisting of poly(ethylene glycol) (PEG) covalently crosslinked poly(methyl vinyl ether-alt-maleic acid) (P(MVE-alt-MA)) (network 1, denoted as PEMM) and Sr2+ (or Ca2+, Fe3+) ionically cross-linked alginates (network 2, denoted as SrAlg, CaAlg, or FeAlg), were prepared. The stiffness, morphology, and components of the PEMM/alginate hydrogels were systematically investigated to understand their effects on CSC enrichment. Only the PEMM/FeAlg hydrogels could support the long-term growth, proliferation, and spheroid formation of SK-OV-3 cells. The expression of CSC-related markers was evaluated with the levels of protein and gene at different stages. The cell spheroids cultured in the PEMM/FeAlg hydrogels acquired certain CSC-like properties, thus drug resistance was enhanced, especially in the PEMM-1/FeAlg hydrogel. In vivo tumorigenicity experiments also confirmed the presence of more CSCs in the PEMM-1/FeAlg hydrogel. The results suggest that matrix stiffness, morphology, and cations act synergistically on the regulation of the epithelial-mesenchymal transition (EMT), interleukin-6 (IL-6), and Wnt pathways, affecting the invasiveness of ovarian cancer and the conversion of the non-CSCs into CSCs. The PEMM-1/FeAlg hydrogel with lower elastic modulus, a more macroporous morphology, and higher swelling rate can significantly enhance the stemness, malignancy, and tumorigenicity of SK-OV-3 cells

    Impact of Moisture Content on the Dynamic Failure Energy Dissipation Characteristics of Sandstone

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    Rockburst frequently occurs in deep underground engineering, which poses a threat to safety and causes economic losses. Water injection into surrounding rock masses is an effective method for preventing rockburst, and the moisture content of rocks is significant for assessing the probability of rockburst. However, the majority of studies focus on the relationship between the macromechanical properties of rock masses under static loads and the moisture content of rock masses and seldom explore the impact of moisture variation (under dynamic loads) on the mechanical properties and energy dissipation. In this paper, the mechanical properties and energy dissipation of sandstone with different moisture contents have been experimentally investigated by the split Hopkinson pressure bar (SHPB) test. The test results indicate that the peak strength, dynamic elastic modulus, and unloading elastic modulus of sandstone in dry conditions are considerably larger than those in moisture conditions, and the three parameters linearly decrease as the moisture content increases from 0% to 2.58%. The distribution law of sandstone fragments with different moisture contents has been investigated by sieving test fragments with different grain sizes of grading sieves. The results show that the percentage of large grain size fragments incrementally decreases, and the percentage of small grain size fragments incrementally increases with moisture contents from 0% to 2.58%. When the moisture content ranges from 2.01%∼2.58%, the fractal dimension linearly increases, which indicates that the higher the moisture content is, the larger the dimension of the broken sandstone is. The calculation results for energy indicate that the sandstone energy attains the peak value with 0% moisture content. When the moisture content ranges from 2.01%∼2.58%, the reflected energy increases, and the transmitted energy and dissipated energy linearly decrease. In addition, the surface energy of the sandstone with different moisture contents has been investigated by converting fragments into spheres with the corresponding size. The results indicate that the smallest surface area of sandstone is obtained in dry conditions, but its surface energy in dry conditions is larger than that in moisture conditions. When the moisture ranges from 0% to 2.58%, due to 3% illite and 2% chlorite clay minerals reacting with different proportions of moisture, the surface areas of sandstone fragments linearly increase and the surface energy of sandstone linearly decreases

    Expansion of Ovarian Cancer Stem-like Cells in Poly(ethylene glycol)-Cross-Linked Poly(methyl vinyl ether-alt-maleic acid) and Alginate Double-Network Hydrogels

    No full text
    A better understanding of cancer stem cells (CSCs) is essential for research on cancer therapy and drug resistance. Currently, increasingly more investigations are focused on obtaining CSCs to study the mechanism of their enhanced malignancy. In this work, three kinds of double-network hydrogels (PEMM/alginate), consisting of poly(ethylene glycol) (PEG) covalently crosslinked poly(methyl vinyl ether-alt-maleic acid) (P(MVE-alt-MA)) (network 1, denoted as PEMM) and Sr2+ (or Ca2+, Fe3+) ionically cross-linked alginates (network 2, denoted as SrAlg, CaAlg, or FeAlg), were prepared. The stiffness, morphology, and components of the PEMM/alginate hydrogels were systematically investigated to understand their effects on CSC enrichment. Only the PEMM/FeAlg hydrogels could support the long-term growth, proliferation, and spheroid formation of SK-OV-3 cells. The expression of CSC-related markers was evaluated with the levels of protein and gene at different stages. The cell spheroids cultured in the PEMM/FeAlg hydrogels acquired certain CSC-like properties, thus drug resistance was enhanced, especially in the PEMM-1/FeAlg hydrogel. In vivo tumorigenicity experiments also confirmed the presence of more CSCs in the PEMM-1/FeAlg hydrogel. The results suggest that matrix stiffness, morphology, and cations act synergistically on the regulation of the epithelial-mesenchymal transition (EMT), interleukin-6 (IL-6), and Wnt pathways, affecting the invasiveness of ovarian cancer and the conversion of the non-CSCs into CSCs. The PEMM-1/FeAlg hydrogel with lower elastic modulus, a more macroporous morphology, and higher swelling rate can significantly enhance the stemness, malignancy, and tumorigenicity of SK-OV-3 cells
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