Gastric cancer (GC) is one of the main causes of cancer-related death. Lysine acetyltransferases 2 A (KAT2A) is a succinyltransferase that plays an essential role in cancer development. The pyruvate ...kinase M2 (PKM2) is a glycolysis rate-limiting enzyme that mediates the glycolysis of cancers. This study aimed to explore the effects and mechanism of KAT2A in GC progression. The effects of biological behaviors of GC cells were evaluated by MTT, colony formation and seahorse assays. The succinylation modification was assessed by immunoprecipitation (IP). The interaction between proteins were detected by Co-IP and immunofluorescence. A pyruvate kinase activity detection kit was used to evaluate the activity of PKM2. Western blot was performed to detect the expression and oligomerization of protein. Herein, we confirmed that KAT2A was highly expressed in GC tissues and was associated with a poor prognosis. Function studies showed that knockdown of KAT2A inhibited cell proliferation and glycolytic metabolism of GC. Mechanistically, KAT2A could directly interacted with PKM2 and KAT2A silencing inhibited the succinylation of PKM2 at K475 site. In addition, the succinylation of PKM2 altered its activity rather than its protein levels. Rescue experiments showed that KAT2A promoted GC cell growth, glycolysis, and tumor growth by promoting PKM2 K475 succinylation. Taken together, KAT2A promotes the succinylation of PKM2 at K475 to inhibit PKM2 activity, thus promotes the progression of GC. Therefore, targeting KATA2 and PKM2 may provide novel strategies for the treatment of GC.
Broadband antireflection is essential for improving the photocurrent generation of photovoltaic modules or the enhancement of visibility in optical devices. The moth-eye nanostructure is one of the ...most promising structures with potential for commercialization in the near future and roll-to-roll ultraviolet nanoimprint lithography (R2R UV-NIL) technique provides a solution for the commercialization due to its high speed, large area, high resolution, and high throughput. In this study, the anodic aluminum oxide (AAO) mold is used to produce the moth-eye nanostructure arrays upon a flexible polyethylene terephthalate substrate combining with R2R UV-NIL process, which provides a solution for continuous production of moth-eye nanostructure arrays cheaply. In addition, the influence of mold parameters and process parameters on the forming quality were investigated, respectively. The influence of process parameters was investigated by using the one-variable-at-a-time method, including feeding speed, imprinting pressure, and mold temperature. The qualitative and quantitative height evaluation for the moth-eye nanostructure arrays were carried out based on the atomic force microscope images. As a result, the feasibility is verified to produce moth-eye nanostructure arrays continuously with AAO mold and R2R UV-NIL technique. A rapid feeding speed of 20 m/min was possible to produce good moth-eye nanostructure arrays with mold 1, which were 300 nm in diameter, 300 nm in height. However, different forming results were observed as the mold parameters decreased including unsatisfactory demolding phenomenon and incomplete filling phenomenon. The incomplete filling phenomenon was improved to a certain extent by changing the process parameters and higher forming height was accomplished with lower feeding speed, higher imprinting pressure, and higher mold temperature. This research is beneficial to provide a direction for the industrial production of the moth-eye nanostructure arrays.
We present a submillimeter continuum survey ("SCUBA2 High rEdshift bRight quasaR surveY," hereafter SHERRY) of 54 high-redshift quasars at 5.6 < z < 6.9 with quasar bolometric luminosities in the ...range of (0.2-5) × 1014 L , using the Submillimetre Common-User Bolometer Array-2 (SCUBA2) on the James Clerk Maxwell Telescope. About 30% (16/54) of the sources are detected with a typical 850 m rms sensitivity of 1.2 mJy beam−1 (S ,850 m = 4-5 mJy, at >3.5 ). The new SHERRY detections indicate far-infrared (FIR) luminosities of 3.5 × 1012 to 1.4 × 1013 L , implying extreme star formation rates of 90-1060 M yr−1 in the quasar host galaxies. Compared with z = 2-5 samples, the FIR-luminous quasars (LFIR > 1013 L ) are rarer at z ∼ 6. The optical/near-infrared spectra of these objects show that 11% (6/54) of the sources have weak Ly emission-line features, which may relate to different subphases of the central active galactic nuclei (AGNs). Our SCUBA2 survey confirms the trend reported in the literature that quasars with submillimeter detections tend to have weaker ultraviolet (UV) emission lines compared to quasars with nondetections. The connection between weak UV quasar line emission and bright dust continuum emission powered by massive star formation may suggest an early phase of AGN-galaxy evolution, in which the broad-line region is starting to develop slowly or is shielded from the central ionization source, and has unusual properties such as weak-line features or bright FIR emission.
The study on the relationship of abandoned settlements and climate change in the oases could provide a historical reference for understanding human responses to present and future global warming in ...the arid zone. A total of 554 abandoned historical settlements in Xinjiang Uygur Autonomous Region, China, were used to examine the relationship between abandoned settlements and temperature change over the past 2000 years. The analysis covered dynastic epochs from the Han Dynasty （206BC-220AD） to the Qing Dynasty （1644AD- 1911AD） in the oases of Xinjiang. Greater density of settlements was found at the oases larger than 2000 km^2, which were more stable and less sensitive to climate change compared to smaller oases. Settlements flourished at small oases and the middle and lower reaches of rivers during warm periods and shrank back to piedmont basins and upstream alluvial fans during cold periods. These results demonstrated responses of oasis agriculture to climate change.
The construction of a highly sensitive and reproducible surface-enhanced Raman scattering (SERS) substrate is the key factor that restricts its practical application. In this paper, a ...three-dimensional (3D) SERS substrate based on ordered micropyramid array and silver nanoparticles (MPA/AgNPs 3D-SERS) was constructed using the roll-to-plate embossing technology and a hydrothermal method, which provided an efficient and low-cost preparation process for the SERS substrate. Using rhodamine 6G (R6G) as a probe molecule, the performance of an MPA/AgNP 3D-SERS substrate was studied in detail, whose minimum detection limit was 10–12 M and the enhancement factor was calculated as 8.8 × 109, indicating its high sensitivity. In addition, the minimum relative standard deviation (RSD) for the MPA/AgNP 3D-SERS substrate was calculated as 4.99%, and SERS performance basically had no loss after 12 days of placement, which indicated that the prepared SERS substrate had excellent stability and repeatability. At last, the thiram detection application of the MPA/AgNP 3D-SERS substrate was also investigated. The results showed that the minimum detection limit was 1 × 10–7 M, and quantitative analysis of pesticide residues could be realized. This research could provide useful guidance for the efficient and low-cost fabrication of highly sensitive and reproducible SERS substrates.
Foams have been used as fracking fluids for decades, but their thermodynamic instability has always restricted subsurface applications, particularly in harsh reservoir conditions. Therefore, this ...study comprehensively investigated the role of commonly used stabilizers in foaming behaviors, including the surfactant (APG), nanoparticle (CNCs), and polymer (XG), and their stabilizing behavior at the interface was also explored using molecular dynamics (MD) simulations. Our findings indicated that the 0.5% XG-enhanced Pickering foam (0.5% APG + 1.0% CNCs) would be an exceptional fluid for fracking applications. The formation of APG–CNC–XG gel-like networks among bubbles significantly improved the stability of this liquid foam, and the liquid half-life could be extended by nearly 24 h, while the foam can last for several days at 80 °C. Using MD simulations, we showed that the coexistence and intramolecular interactions among APG, CNCs, and XG molecules generate a stronger hydrogen bonding network in the thin film, significantly reducing water mobility, corresponding to the experimental observations. To explore the potential of foams as fracking fluids, the sand-carrying capacity of two types of foams was also evaluated; the polymer-enhanced Pickering foam was able to suspend the sands for more than a day without participation. In the lab fracturing test, despite requiring a higher breakdown pressure, the polymer-enhanced Pickering foam reduces water consumption by almost 20%. Moreover, the highly viscous foam also induced the wing-shaped fracture with a wider width along the hole. The deep insights gained from this study will advance the application of foams as the fracking fluid in unconventional oil/gas reservoirs.
Android app clone detection has been extensively studied in our community, and a number of effective approaches and frameworks were proposed and released. However, there still remains one open ...challenge that has not been well addressed in previous work, i.e., the authorship attribution for the detected app clones. Although state-of-the-art approaches could accurately identify repackaged apps in one way or another, no convincing method has been proposed to identify the original app and the authentic author from the repackaged app pairs, which greatly limits the usage scenario of app clone detection techniques. For example, app market maintainers have to manually confirm the identified repackaged app pairs, while in most cases, it is challenging for them to make an accurate decision. In this paper, we propose AppAuth, a novel learning-based approach to predict the authorship of app clones. To be specific, for a given Android app clone pair (or a group of repackaged apps identified), AppAuth could accurately infer the original author of the plagiarized apps. Our approach is motivated by the traditional authorship attribution studies on binary files. AppAuth first extracts a number of coding-style-related features from the executable .apk files, and then relies on machine learning techniques to train a classification model. We have conducted extensive experiments to evaluate the effectiveness of AppAuth. The experiment results suggest that we are able to infer the authorship for Android app clones with high precision. Our work is the first one that tackles the problem systematically and we believe our efforts could positively contribute to the research community and boost the research of app repacking detection and authorship attribution studies.
As nanoscale extracellular vesicles, exosomes are secreted by various cell types, and they are widely distributed in multiple biological fluids. Studies have shown that tumor-derived exosomes can ...carry a variety of primary tumor-specific molecules, which may represent a novel tool for the early detection of cancer. However, the clinical translation of exosomes remains a challenge due to the requirement of large quantities of samples when enriching the cancer-related exosomes in biological fluids, the insufficiency of traditional techniques for exosome subpopulations, and the complex exosome isolation of the current commercially available exosome phenotype profiling approaches. The evolving surface-enhanced Raman scattering (SERS) technology, with properties of unique optoelectronics, easy functionalization, and the particular interaction between light and nanoscale metallic materials, can achieve sensitive detection of exosomes without large quantities of samples and multiplexed phenotype profiling, providing a new mode of real-time and noninvasive analysis for cancer patients. In the present review, we mainly discussed exosome detection based on SERS, especially SERS immunoassay. The basic structure and function of exosomes were firstly introduced. Then, recent studies using the SERS technique for cancer detection were critically reviewed, which mainly included various SERS substrates, biological modification of SERS substrates, SERS-based exosome detection, and the combination of SERS and other technologies for cancer diagnosis. This review systematically discussed the essential aspects, limitations, and considerations of applying SERS technology in the detection and analysis of cancer-derived exosomes, which could provide a valuable reference for the early diagnosis of cancer through SERS technology.
Surface-enhanced Raman scattering (SERS) has been applied to exosomes detection to obtain better diagnostic results. In past three years, several reviews have been published in exosome detection, which were narrowly focus on methods of exosome detection. Selection and surface functionalization of the substrate and the combination detection with different methods based on SERS will provide new strategies for the detection of exosomes. This review will focus on the above aspects. This emerging detection method is constantly evolving and contributing to the early discovery of diseases in the future.
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CO2 injection into coal seams can not only enhance the recovery of coalbed methane, but also achieve the goal of CO2 geological sequestration, reducing greenhouse gas emissions. CO2 is likely to be ...stored in the form of supercritical state, when the burial depth of coal seams exceeds 800 m. However, the existing knowledge is still lacking regarding how supercritical CO2 (SC–CO2) reacts with coal. In this work, alterations of pore structure and mineral compositions induced by SC-CO2 interactions have been explored. The results show that coal pore volume and porosity are greatly increased after SC-CO2 interactions, which contributes to the increase of gas adsorption. A comparison of pore fractal dimension has been made between raw coal and treated samples, suggesting that SC-CO2 interaction can enhance pore roughness and structure complexity. XRD analysis indicates that mineral content within coal is remarkably changed after SC-CO2 saturation. Carbonate minerals are sensitive to SC-CO2 fluids, and mineral consumption plays a key role in pore alterations. There are multiple effects of SC-CO2 fluids on both mineral compositions and pore distribution. Mineral dissolution, differential swelling, hydrocarbon extraction and migration account for the variations of coal microstructures and mineral content. The increase in pore volume and structure complexity of coal seams after interaction is quite favorable for CO2 adsorption and storage. This result provides powerful support for CO2 geological sequestration and CO2-ECBM.
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•Pore size distribution of treated coal samples shifts to the smaller pores.•SC-CO2 interaction enhances the pore roughness and structure complexity.•Carbonate minerals in coal are most sensitive to SC-CO2 fluids.•Mineral dissolution plays a key role in the pore alterations.
With its low viscosity properties, CO2 has much greater penetration capacity into micro-fractures, and therefore has more potential to create expanded and effective fractures in shales during the ...hydraulic fracturing process. However, the feasibility of this technique is dependent on the accurate prediction of formation flow characteristics, given the high leak-off of CO2 at deep depths. The aim of this study is therefore to understand the flow behavior of CO2 in deep shale plays. A series of tri-axial permeability tests was conducted under both steady-state and transient conditions. The test results show much lower permeability values for liquid CO2 than gaseous CO2, and the permeability under transient conditions is much lower than that under steady-state conditions, due to the combined effects of the reduced slip-flow effect under low pressures and the temperature variation influence under steady-state conditions. Under steady-state conditions, unstable flow behavior occurred at higher injection pressure (≥9 MPa) possibly due to the fine mineral particle migration and the deposition of small drikold particles, which indicates the serious error in permeability calculation under steady-state conditions. Importantly, a greater than 1 effective stress coefficient (χ) for permeability in tested siltstone was observed, confirming the greater sensitivity of CO2 to pore pressure than confining pressure.
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