An iron-rich pre-alloyed powder was selected out, and the pre-alloying degree of matrix materials and the sintering temperature were considered to investigate the effect of the Fe-based pre-alloyed ...powder on the microstructure and holding strength of impregnated diamond bit matrix. And relative density and bending strength of the specimens were measured, and then the resulting fracture surfaces were analyzed using scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The results showed that the relative density, bending strength and plasticity of matrix materials are increased with the sintering temperature and the pre-alloying degree. The influence of the pre-alloying degree on them is more significant than that of the sintering temperature within the experimental parameters. Besides, Fe-based matrices have thermal corrosion effect on diamonds at high temperature sintering process. And the rate of diamond graphitization has a greatly increase with the sintering temperature changes from 900 °C to 1020 °C and the holding strength decreases. A low pre-alloying degree accelerates the rate of diamond graphitization. But an adequate pre-alloying degree of Fe-based matrix materials is conducive to improve the wettability of the matrix to diamonds, alleviate the diamond graphitization, reduce the diamonds' thermal damage and improve the holding strength. Besides, it can also greatly reduce the sintering temperature and broaden the sintering temperature range. In a word, it is feasible and reasonable that Fe-based pre-alloyed powders replace Fe elemental powders to fabricate impregnated diamond bits. And it has a good economic value and broad application prospect.
•The relative density, bending strength and plasticity of the matrix were studied.•They are increased with the sintering temperature and the pre-alloying degree.•A low pre-alloying degree accelerates the rate of diamond graphitization.•A high pre-alloying degree reduces the graphitization and improves the holding force.•It can also greatly reduce the sintering temperature and broaden the sintering range.
Melanoma is a fatal skin malignant tumor with a poor prognosis. We found that long noncoding RNA BASP1‐AS1 is essential for the development and prognosis of melanoma. The methylation, RNA sequencing, ...copy number variation, mutation data, and sample follow‐up information of melanoma from The Cancer Genome Atlas (TCGA) were analyzed using weighted gene co‐expression network analysis and 366 samples common to the three omics were selected for multigroup clustering analysis. A four‐gene prognostic model (BASP1‐AS1, LOC100506098, ARHGAP27P1, and LINC01532) was constructed in the TCGA cohort and validated using the GSE65904 series. The expression of BASP1‐AS1 was upregulated in melanoma tissues and various melanoma cell lines. Functionally, the ectopic expression of BASP1‐AS1 promoted cell proliferation, migration, and invasion in both A375 and SK‐MEL‐2 cells. Mechanically, BASP1‐AS1 interacted with YBX1 and recruited it to the promoter of NOTCH3, initiating its transcription process. The activation of the Notch signaling then resulted in the transcription of multiple oncogenes, including c‐MYC, PCNA, and CDK4, which contributed to melanoma progression. Thus, BASP1‐AS1 could act as a potential biomarker for cutaneous malignant melanoma.
We identified a new type of long noncoding RNA (LncRNA) BASP1‐AS1, which can promote melanoma development both in vivo and in vitro. Detailed studies on the molecular mechanism showed that BASP1‐AS1 promoted the proliferation, invasion, and migration of melanoma cells by regulating YBX1. In addition, LncRNA BASP1‐AS1 is a poor prognostic indicator and a potential therapeutic target for melanoma.
In single-cell RNA sequencing (scRNA-seq), doublets form when two cells are encapsulated into one reaction volume. The existence of doublets, which appear to be—but are not—real cells, is a key ...confounder in scRNA-seq data analysis. Computational methods have been developed to detect doublets in scRNA-seq data; however, the scRNA-seq field lacks a comprehensive benchmarking of these methods, making it difficult for researchers to choose an appropriate method for specific analyses. We conducted a systematic benchmark study of nine cutting-edge computational doublet-detection methods. Our study included 16 real datasets, which contained experimentally annotated doublets, and 112 realistic synthetic datasets. We compared doublet-detection methods regarding detection accuracy under various experimental settings, impacts on downstream analyses, and computational efficiencies. Our results show that existing methods exhibited diverse performance and distinct advantages in different aspects. Overall, the DoubletFinder method has the best detection accuracy, and the cxds method has the highest computational efficiency. A record of this paper’s transparent peer review process is included in the Supplemental Information.
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•Benchmark of nine computational doublet-detection methods for scRNA-seq data•Evaluation based on the most comprehensive set of real data with labeled doublets•Diverse performance and distinct advantages of different doublet-detection methods•DoubletFinder excels in detection accuracy; cxds leads in computational efficiency
We conduct a systematic benchmark study of nine cutting-edge computational doublet-detection methods. We evaluate the methods’ detection accuracy, impacts on downstream analyses, and computational efficiency, using a comprehensive set of real and synthetic data. Although no method dominates in all aspects, the DoubletFinder and cxds methods have the best detection accuracy and computational efficiency, respectively.
Long-term grazing profoundly affects grassland ecosystems, whereas how the soil microbiome and multiple soil ecosystem functions alter in response to two-decades of grazing, especially how soil ...microbiome (diversity, composition, network complexity, and stability) forms soil multifunctionality is rarely addressed.
We used a long-term buffalo grazing grassland to measure the responses of soil physicochemical attributes, stoichiometry, enzyme activities, soil microbial niche width, structure, functions, and networks to grazing in a subtropical grassland of Guizhou Plateau, China.
The evidence from this work suggested that grazing elevated the soil hardness, available calcium content, and available magnesium content by 6.5, 1.9, and 1.9 times (
= 0.00015-0.0160) and acid phosphatase activity, bulk density, pH by 59, 8, and 0.5 unit (
= 0.0014-0.0370), but decreased the soil water content, available phosphorus content, and multifunctionality by 47, 73, and 9-21% (
= 0.0250-0.0460), respectively. Grazing intensified the soil microbial carbon limitation (+78%,
= 0.0260) as indicated by the increased investment in the soil β-glucosidase activity (+90%,
= 0.0120). Grazing enhanced the complexity and stability of the bacterial and fungal networks but reduced the bacterial Simpson diversity (
< 0.05). The bacterial diversity, network complexity, and stability had positive effects, while bacterial and fungal compositions had negative effects on multifunctionality.
This work is an original attempt to show that grazing lowered multifunctionality
the reduced bacterial diversity and shifted soil bacterial and fungal compositions rather than the enhanced bacterial and fungal network complexities and stability by grazing. Protecting the bacterial diversity from decreasing, optimizing the composition of bacteria and fungi, and enhancing the complexity and stability of bacterial network may be conducive to improving the soil multifunction of grazing grassland, on a subtropical grassland.
With the substantially growing trend of the aging populations in China and the rest of the world, the number of total hip and total knee arthroplasty (THA and TKA) cases are increasing dramatically. ...It is important to develop practical strategies to improve the quality of healthcare and better outcome for patients undergoing THA and TKA. Enhanced recovery after surgery (ERAS) pathways have been reported to promote earlier recovery and be beneficial for patients. We propose the hypothesis that the ERAS pathway could reduce the length of stay (LOS) in hospital for patients undergoing primary THA or TKA.
This trial is a prospective, open-labelled, multi-centered, randomized controlled trial that will test the superiority of the ERAS pathway in term of LOS in hospital for the patients undergoing primary THA or TKA compared to current non-ERAS clinical practice. A total of 640 patients undergoing primary THA or TKA will be randomly allocated to either ERAS pathway (ERAS group) or conventional care according to individual participating center (non-ERAS group). The primary outcome is the total LOS in hospital; the secondary outcomes include postoperative LOS, all-cause mortality by 30 days after operation, in-hospital complications, early mobilization, postoperative pain control, total in-hospital cost, and readmission rate by 30 days after discharge from the hospital.
This trial is designed to evaluate the superiority of the ERAS pathway to conventional non-ERAS clinical practice in reducing the LOS. The results may provide new insight into the clinical applications of the ERAS pathway for THA and TKA.
National Institutes of Health Clinical Trials Registry, NCT03517098 . Registered on 4 May 2018.
Quercetin, a dietary antioxidant present in fruits and vegetables, is a promising cancer chemopreventive agent that inhibits tumor promotion by inducing cell cycle arrest and promoting apoptotic cell ...death. In this study, we examined the biological activities of quercetin against gastric cancer. Our studies demonstrated that exposure of gastric cancer cells AGS and MKN28 to quercetin resulted in pronounced pro-apoptotic effect through activating the mitochondria pathway. Meanwhile, treatment with quercetin induced appearance of autophagic vacuoles, formation of acidic vesicular organelles (AVOs), conversion of LC3-I to LC3-II, recruitment of LC3-II to the autophagosomes as well as activation of autophagy genes, suggesting that quercetin initiates the autophagic progression in gastric cancer cells. Furthermore, either administration of autophagic inhibitor chloroquine or selective ablation of atg5 or beclin 1 using small interfering RNA (siRNA) could augment quercetin-induced apoptotic cell death, suggesting that autophagy plays a protective role against quercetin-induced apoptosis. Moreover, functional studies revealed that quercetin activated autophagy by modulation of Akt-mTOR signaling and hypoxia-induced factor 1α (HIF-1α) signaling. Finally, a xenograft model provided additional evidence for occurrence of quercetin-induced apoptosis and autophagy in vivo. Together, our studies provided new insights regarding the biological and anti-proliferative activities of quercetin against gastric cancer, and may contribute to rational utility and pharmacological study of quercetin in future anti-cancer research.
Phytoplankton blooms have caused many serious public safety incidents and eco-environmental problems worldwide and became a focus issue for research. Accurate and rapid monitoring of phytoplankton ...blooms is critical for forecasting, treating, and management. With the advantages of large spatial coverage and high temporal resolution, remote sensing has been widely used to monitor phytoplankton blooms. Numerous advances have been made in the remote sensing of phytoplankton blooms, biomass, and phenology over the past several decades. To fully understand the development history, research hotspots, and future trends of remote-sensing technology in the study of phytoplankton blooms, we conducted a comprehensive review to systematically analyze the research trends in the remote sensing of phytoplankton blooms through bibliometrics. Our findings showed that research on the use of remote-sensing technology in this field increased substantially in the past 30 years. “Oceanography,” “Environmental Sciences,” and “Remote Sensing” are the most popular subject categories. Remote Sensing of Environment, Journal of Geophysical Research: Oceans, and International Journal of Remote Sensing were the journals with the most published articles. The results of the analysis of international influence and cooperation showed that the United States had the greatest influence in this field and that the cooperation between China and the United States was the closest. The Chinese Academy of Sciences published the largest number of papers, reaching 542 articles. Keyword and topic analysis results showed that “phytoplankton,” “chlorophyll,” and “ocean” were the most frequently occurring keywords, while “eutrophication management and monitoring,” “climate change,” “lakes,” and “remote-sensing algorithms” were the most popular research topics in recent years. Researchers are now paying increasing attention to the phenological response of phytoplankton under the conditions of climate change and the application of new remote-sensing methods. With the development of new remote-sensing technology and the expansion of phytoplankton research, future research should focus on (1) accurate observation of phytoplankton blooms; (2) the traits of phytoplankton blooms; and (3) the drivers, early warning, and management of phytoplankton blooms. In addition, we discuss the future challenges and opportunities in the use of remote sensing in phytoplankton blooms. Our review will promote a deeper and wider understanding of the field.
China has been troubled by high concentrations of fine particulate matter (PM2.5) for many years. Up to now, the pollutant sources are not yet fully understood and the control approach still remains ...highly uncertain. In this study, four month-long (January, April, July and October in 2015) WRF-Chem simulations with different sensitivity experiments were conducted in the Yangtze River Delta (YRD) region of eastern China. The simulated results were compared with abundant meteorological and air quality observations at 138 stations in 26 YRD cities. Our model well captured magnitudes and variations of the observed PM2.5, with the normal mean biases (NMB) less than ±20% for 19 out of the 26 YRD cities. A series of sensitivity simulations were conducted to quantify the contributions from individual source sectors and from different regions to the PM2.5 in the YRD region. The calculated results show that YRD local source contributed 64% of the regional PM2.5 concentration, while outside transport contributed the rest 36%. Among the local sources, industry activity was the most significant sector in spring (25%), summer (36%) and fall (33%), while residential source was more important in winter (38%). We further conducted scenario simulations to explore the potential impacts of varying degrees of emission controls on PM2.5 reduction. The result demonstrated that regional cooperative control could effectively reduce the PM2.5 level. The proportionate emission controls of 10%, 20%, 30%, 40% and 50% could reduce the regional mean PM2.5 concentrations by 10%, 19%, 28%, 37% and 46%, respectively, and for places with higher ambient concentrations, the mitigation efficiency was more significant. Our study on source apportionment and emission controls can provide useful information on further mitigation actions.
It has been observed that since the Early Qing Dynasty, the eastward spread of Western classics has been in decline; this article aims to looks at how Protestant missionaries helped to revive it in ...the late nineteenth and early twentieth centuries. First, this study examines the circumstances that Protestant missionaries faced upon arriving in China and describes the challenges, opportunities, and issues they encountered when attempting to spread Western classics as part of their missionary effort. Second, this article reveals the strategies Protestant missionaries employed to revive the Western classics, with a focus on the utilization of the translated literature, press, and academic institutions. Third, this article explores the ways the spread of Western classics by the missionaries of the late nineteenth and early twentieth century outshone the achievements of their predecessors of the late sixteenth and seventeenth centuries. Unlike the missions through secular knowledge in China, the spread of Protestantism in Korea took place in a more direct manner. This comparative study in the last section highlights the importance of each country’s endowment in terms of the method and effectiveness of missionary efforts.
Estimating and accounting for hidden variables is widely practiced as an important step in molecular quantitative trait locus (molecular QTL, henceforth "QTL") analysis for improving the power of QTL ...identification. However, few benchmark studies have been performed to evaluate the efficacy of the various methods developed for this purpose.
Here we benchmark popular hidden variable inference methods including surrogate variable analysis (SVA), probabilistic estimation of expression residuals (PEER), and hidden covariates with prior (HCP) against principal component analysis (PCA)-a well-established dimension reduction and factor discovery method-via 362 synthetic and 110 real data sets. We show that PCA not only underlies the statistical methodology behind the popular methods but is also orders of magnitude faster, better-performing, and much easier to interpret and use.
To help researchers use PCA in their QTL analysis, we provide an R package PCAForQTL along with a detailed guide, both of which are freely available at https://github.com/heatherjzhou/PCAForQTL . We believe that using PCA rather than SVA, PEER, or HCP will substantially improve and simplify hidden variable inference in QTL mapping as well as increase the transparency and reproducibility of QTL research.
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