Volatile methyl siloxanes (VMS), which are considered to be the most troublesome impurities in current biogas-cleaning technologies, need to be removed. In this study, we fabricated a series of ...Fesub.3Osub.4–urea-modified reduced graphene-oxide aerogels (Fesub.3Osub.4–urea–rGOAs) by using industrial-grade graphene oxide as the raw material. A fixed-bed dynamic adsorption setup was built, and the adsorption properties of the Fesub.3Osub.4–urea–rGOAs for hexamethyldisiloxane (L2, as a VMS model pollutant) were studied. The properties of the as-prepared samples were investigated by employing various characterization techniques (SEM, TEM, FTIR, XRD, Raman spectroscopy, and Nsub.2 adsorption/desorption techniques). The results showed that the Fesub.3Osub.4–urea–rGOA–0.4 had a high specific surface area (188 msup.2 gsup.−1), large porous texture (0.77 cmsup.3 gsup.−1), and the theoretical maximum adsorption capacity for L2 (146.5 mg gsup.−1). The adsorption capacity considerably increased with a decrease in the bed temperature of the adsorbents, as well as with an increase in the inlet concentration of L2. More importantly, the spent Fesub.3Osub.4–urea–rGOA adsorbent could be readily regenerated and showed an excellent adsorption performance. Thus, the proposed Fesub.3Osub.4–urea–rGOAs are promising adsorbents for removing the VMS in biogas.
Aiming at the problem of the evaluation of College Chinese teaching, based on the development of internet of things technology, this paper discusses the teaching rules of internet of things ...technology in detail and makes relevant analysis. Then, college students of different grades are selected and applied to the specific evaluation of College Chinese teaching based on internet of things technology. The experimental results show that college students of different grades have different effects on College Chinese teaching based on internet of things technology. In addition, in the process of College Chinese teaching, freshmen and sophomores have a positive evaluation of the effect of Chinese teaching and have a strong interest in Chinese learning while senior students have the worst evaluation and interest in learning. Finally, the paper analyzes the possible problems in the evaluation of College Chinese teaching based on internet of things technology.
•V2O3@C composites were prepared by the pyrolyzed of the soluble starch with V2O5.•It exhibits high PCE of 5.13 % than 4.54% of Pt CEs based DSSC.•V2O3@C composites are a prospective alternative of ...Pt-free CEs in DSSCs.
The traditional counter electrodes (CEs) catalysts are mainly noble Pt-based materials, but their scarcity and high cost impede their practical applications, especially in dye sensitized solar cells (DSSCs). Hence, identifying Pt-free catalyst materials for CEs have been regarded as one of the crucial steps to improve energy conversion efficiency and cost effectiveness of DSSCs. Herein, a feasible one-step reduction was put forward to prepare V2O3@C composites utilizing V2O5 as metal sources, and the soluble starch as carbon source. The four V2O3@C composite catalysts have successfully been prepared and further were applied to CEs as catalytic materials in the encapsulation of DSSCs. The power conversion efficiencies (PCE) of 2.79, 3.94, 5.13 and 4.97% were respectively obtained from mass ratios of the soluble starch to V2O5 with 1:2, 1:1, 2:1 and 4:1 as counter electrode for the regeneration of I3−/I− redox couples. The enhanced performance can be ascribed to the number of active catalytic sites and the distribution channels on the V2O3@C composites CEs, which was caused by that the larger surface area and higher conductivity of amorphous C from the pyrolyzed carbonization of the soluble starch in the precursor.
The temporal and spatial characteristics of soil moisture over the Tibetan Plateau (TP) were analysed to explore the relative contributions of temperature and precipitation to soil moisture change. ...Non-significant changes in soil moisture were observed for the TP over the period 1950-2010, while a seasonal cycle was evident, with higher values in summer and smaller values in winter. The soil moisture showed obvious spatial heterogeneity, with higher values in the south than in the north of the TP. The soil moisture fluctuated with time, jointly influenced by precipitation and temperature changes, with precipitation the dominant factor, while temperature regulated the relationship between soil moisture and precipitation. The relative contribution of precipitation to soil moisture changes was over 80%, except for winter in which temperature was the dominant factor, with a relative contribution of more than 70%. Because of the sharp increase in temperature in winter, the uneven spatial distribution of soil moisture over the TP might harm the fragile ecological environment.
Cardiovascular disease (CVD) is one of the main causes of premature death in patients with schizophrenia. High-sensitivity C-reactive protein (hs-CRP) is closely related to various risk factors of ...CVD in the general population and is a sensitive marker of subclinical inflammation.
The study intended to evaluate the predictive value of hs-CRP for high cardiovascular risk in patients with schizophrenia.
The research team designed a cross-sectional retrospective study.
The study took place at the Affiliated Brain Hospital of Guangzhou Medical University in Guangzhou, Guangdong Province, China.
Participants were 387 patients with schizophrenia who had been admitted to the inpatient clinic at the hospital between January 1, 2018 and December 30, 2019.
The research team: (1) measured participants' hs-CRP and calculated the 10-year general cardiovascular risk, with a risk of >20% being defined as a high risk; (2) compared participants' demographics and traditional cardiovascular risk factors, and the prevalence of high cardiovascular risk according to the hs-CRP quartile; (3) used the receiver operating characteristic (ROC) curves to determine the optimal cutoff value for hs-CRP to predict high cardiovascular risk; and (4) used multivariate logistic regression analysis to assess the association between hs-CRP and high cardiovascular risk.
Of the 387 participants, 23 had a high cardiovascular risk (5.9%). The prevalence of high cardiovascular risk in quartiles Q1, Q2, Q3, and Q4 groups was 0%, 2.0%, 12.5%, and 9.4%, respectively, with a P trend < .001. The ROC analysis showed that an hs-CRP cutoff value of 2.13mg/L was a fair discriminator for high cardiovascular risk, with a C statistic of 0.74. After adjusting confounding factors by multivariate logistic regression analysis, an hs-CRP of ≥2.13 mg/L was significantly associated with high cardiovascular risk (OR = 7.81, 95% CI: 1.73 - 35.39, P = .008).
An hs-CRP of ≥2.13 mg/L can be an independent predictor of high cardiovascular risk in patients with schizophrenia. Detection of hs-CRP may be beneficial in identifying patients at high risk of cardiovascular events in this population. Further prospective studies are needed to determine the hs-CRP threshold for evaluating cardiovascular risk in schizophrenia.
Both droughts and tropical cyclones (TCs) are among the world's most widespread natural disasters. This paper is concentrated on the effects of TCs on the links between meteorological droughts (MDs) ...and agricultural droughts (ADs). Specifically, changes in characteristics of drought events and variations in propagation features of matched MD and AD event pairs are quantified by using the renowned three-dimensional connected components algorithm; both alleviation and exacerbation effects of TCs are evaluated; and the Spearman's correlation is employed to identify potential contributors to exacerbated droughts after TCs. The results show that TCs exhibit more pronounced and widespread alleviation effects on MD events compared to AD events. >98 % of small-scale drought events are terminated by TCs, leading to 65 % reduction in the total area of MD events smaller than 50,000 km2 and 32 % reduction in AD events of the same scale. In the meantime, TCs can reshape the spatiotemporal links between MDs and ADs by reducing the overall propagation rate from 77 % to 40 % and ameliorating the characteristics of drought event pairs with higher propagation efficiency, by >40 %. After TCs, over 55 % of drought exacerbations in TC-affected regions occur first in the vicinity of the residual large-scale AD events. This occurrence is partially associated with the reduction in moisture exports from these residual droughts downwind to the interior of TC-affected regions, a process potentially facilitated by the TC-induced temperature cooling. The in-depth evaluation of this paper presents useful information for better drought preparation and mitigation under TCs.
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•Three-dimensional effects of tropical cyclones on drought propagation are investigated in China.•Over 98 % of drought events smaller than 50,000 km2 are terminated by tropical cyclones.•Propagation rate from meteorological drought to agricultural drought is reduced from 77 % to 40 %.
Hybridization chain reaction (HCR) based enzyme-free amplification techniques have recently been developed for the visualization of intracellular messenger RNA (mRNA). However, the slow kinetics and ...potential interference with the intricate biological environments hinder its application in the clinic and in vivo. Herein, we designed a nanofirecracker probe-based strategy using intramolecular hybridization chain reaction (IHCR) amplifier for rapid, efficient, sensitive, specific detection and imaging of survivin mRNA both in vitro and vivo. Two probes, HP1 and HP2, in IHCR were simultaneously incorporated into a DNA nanowire scaffolds to bring HP1 and HP2 to close proximity on the assembled nanowire scaffolds. Empowered by the DNA nanowire scaffolds and spatial confinement effect, the nanofirecracker probe-based IHCR sensing system exhibited improved biostability, accelerated reaction kinetics, and enhanced signal amplification. This new strategy has been successfully applied to imaging mRNA in both cultured cells and in mice. Importantly, this novel sensing method was capable of detecting survivin mRNA in clinical blood samples from subjects with colorectal cancer. Thus, this novel nanofirecracker probe-based IHCR strategy holds great potential in advancing both biomedical research and in molecular diagnostics.
MicroRNAs (miRNAs) have been identified as important biomarkers with great significance for diagnosis and treatment of various diseases. However, their unique properties, such as small size, high ...sequence homology, and low abundance, make quantitative analysis of miRNAs extremely challenging. Herein, we reported a cascade catalytic hairpin assembly (CCHA) for sensitive and selective detection of miRNA with three kinds of hairpin probes (HP1, HP2, and HP3). In the presence of target miRNA, a series of toehold-mediated intermolecular DNA strand displacement and hybridization was activated among HP1, HP2, and HP3 to assembly numbers of DNA nanoobjects. During this period, the fluorescence response was greatly intensified to indicate the presence and expression level of interested target miRNA. We have demonstrated that the proposed method exhibits a high assay sensitivity to detect low concentration target and an excellent sequence specificity to distinguish even a single-nucleotide difference in vitro. Moreover, we also demonstrated that our design enables the intracellular imaging of miRNA in live cancer and normal cells. These results showing the promising potential of our CCHA for powerful biosensing, clinic diagnosis, or prognosis.
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•We have developed a target-triggered cascade catalytic hairpin assembly (CCHA) using three hairpin probes.•The CCHA system can be used for robustly detection of miRNA-21.•The CCHA system can be applied to image intracellular miRNA in various types of cell lines.•This unique method holds promising potential for biomedical study and clinical molecular diagnostics.
Developing highly efficient and reliable methods for simultaneous imaging of microRNAs in living cells is often appealed to understanding their synergistic functions and guiding the diagnosis and ...treatment of human diseases, such as cancers. In this work, we rationally engineered a four-arm shaped nanoprobe that can be stimuli-responsively tied into a Figure-of-Eight nanoknot via spatial confinement-based dual-catalytic hairpin assembly (SPACIAL-CHA) reaction and applied for accelerated simultaneous detection and imaging of different miRNAs in living cells. The four-arm nanoprobe was facilely assembled from a cross-shaped DNA scaffold and two pairs of CHA hairpin probes (21HP-a and 21HP-b for miR-21, while 155HP-a and 155HP-b for miR-155) via the "one-pot" annealing method. The DNA scaffold structurally provided a well-known spatial-confinement effect to improve the localized concentration of CHA probes and shorten their physical distance, resulting in an enhanced intramolecular collision probability and accelerating the enzyme-free reaction. The miRNA-mediated strand displacement reactions can rapidly tie numerous four-arm nanoprobes into Figure-of-Eight nanoknots, yielding remarkably dual-channel fluorescence proportional to the different miRNA expression levels. Moreover, benefiting from the nuclease-resistant DNA structure based on the unique arched DNA protrusions makes the system ideal for operating in complicated intracellular environments. We have demonstrated that the four-arm-shaped nanoprobe is superior to the common catalytic hairpin assembly (COM-CHA) in stability, reaction speed, and amplification sensitivity in vitro and living cells. Final applications in cell imaging have also revealed the capacity of the proposed system for reliable identification of cancer cells (e.g., HeLa and MCF-7) from normal cells. The four-arm nanoprobe shows great potential in molecular biology and biomedical imaging with the above advantages.
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•Four-arm-shaped nanoprobe can be used for simultaneous imaging of different miRNAs.•The SPACIAL-CHA-based system exhibits a high reaction speed and sensitivity.•Arched DNA protrusions have provided the probe an enhanced nuclease resistance.•The technique has applications in molecular diagnosis and biomedical studies.
Reprogramming Tumor‐Associated Macrophages
In article number 2108971, Zhen Li and co‐workers find that ultra‐small Cu2−xSe nanoparticles can effectively polarize tumor‐associated macrophages (TAMs) ...from the tumor‐supportive M2 phenotype into anti‐tumor M1 phenotype to significantly boost anti‐tumor immunity through a novel mechanism. The nanoparticles can generate reactive oxygen species to trigger polarization through the novel ROS‐TRAF6‐IRF5‐IL‐23 signaling pathway, rather than the classic ROS‐NF‐?B‐iNOS pathway.
