A bi-functional sugar-based surfactant ALA14 was designed as the ligand and micelle constructor and demonstrated to promote the copper-catalyzed C-X coupling reaction in water. The nature of this ...micelle, formed by sugar-based surfactants, was investigated with CMC, DLS, and TEM, by which encapsulation and aggregation of the substrates in micelles were verified. Additionally, it was addressed by
1
H-NMR analysis that the enrichment position of the substrates is in the lipophilic alkyl chain. Finally, moderate to excellent yields of the aimed products were obtained in this work. This remarkably simple strategy expanded the scope of C-X coupling reaction in water; most notably, both water and ALA14 can be recycled and reused.
A bi-functional sugar-based surfactant ALA14 was designed as the ligand and micelle constructor and demonstrated to promote the copper-catalyzed C-X coupling reaction in water.
Zn-doped Fe3O4 magnetic nanoparticles represented as Zn x Fe3‑x O4 with different Zn contents of x varying from 0.0 to 1.0 were synthesized using a facile one-step solvothermal method. The Zn/Fe ...ratio in these particles could be accurately controlled using this facile synthesis technique. The ICP-OES and XRD measurements indicated that in the x range from 0 to 0.4 the doped Zn2+ may replace the Fe3+ at the A site and consequently the B-site Fe2+ changed to Fe3+, while above 0.4 the Zn2+ tends to replace the B-site Fe2+. The morphologies and size distributions of these samples characterized from the TEM showed that the nanoparticles appeared to aggregate into magnetic nanocrystal clusters with varying cluster sizes and different Zn doping contents. The magnetic measurement and Mössbauer spectra investigation revealed that the magnetic properties of the Zn x Fe3‑x O4 would exhibit a sensitive dependence with the doped Zn variations. Most importantly, the heat capacity studies illuminated that, at low temperatures, the samples could have a ferromagnetic contribution with x = 0.0 and 0.2 and turn to an antiferromagnetic contribution with x = 0.5, 0.8, and 1.0.
, a traditional Chinese medicine, has been used to treat cardio- and cerebrovascular diseases in China for thousands of years. Flavonoids are major active compounds in
. In this paper, a rapid and ...sensitive ultra-high performance liquid chromatography-triple quadrupole mass spectrometry method was developed and validated for simultaneous determination of 17 flavonoids in
. Quantification was performed by multiple reaction monitoring using electrospray ionization in negative ion mode. Under the optimum conditions, calibration curves for the 17 analytes displayed good linearity (
> 0.9980). The intra- and inter-day precisions (relative standard deviations) were lower than 5.0%. The limit of quantitation ranged from 0.256 to 18.840 ng/mL. The mean recovery range at three spiked concentrations was 94.18-101.97%. The validated approach was successfully applied to 18 samples of
. Large variation was observed for the contents of the 17 analytes. Sativanone and 3'-
-methylviolanone were the dominant compounds. The fragmentation behaviors of six flavonoids were investigated using UPLC with quadrupole time-of-flight tandem mass spectrometry. In negative ion electrospray ionization mass spectrometry, all the flavonoids yielded prominent M - H
ions. Fragments for losses of CH
, CO, and CO
were observed in the mass spectra. Formononetin, liquiritigenin, isoliquiritigenin, sativanone, and alpinetin underwent retro-Diels-Alder fragmentations. The proposed method will be helpful for quality control of
.
Abstract
Computable general equilibrium (CGE) models have been widely employed in economic, social, and environmental impact assessments for low-carbon policies. As net-zero transition has become a ...global trend, it is crucial to conduct a systematic review of how CGE models serve low-carbon policies. This review examined 1002 studies published between 2001 and 2021, revealing the application of CGE models in low-carbon policy analysis by researchers in 51 countries, including the United States, China, Western Europe, Japan, and Australia, while studies in Latin America, Central Asia and Eastern Europe are limited. Climate targets, carbon pricing, and energy policy are the main policy focuses of CGE analysis, while land policy, demand-side actions, and several other policies are less studied. In addition, CGE analysis generally focuses on the economic impacts of carbon reduction, with a growing amount of attention on social and environmental consequences. The structure, database, and model coupling techniques of CGE models are becoming more complex in order to serve the increasingly multifaceted and diverse policy study purposes. This study provides a comprehensive overview of the research trends of CGE studies on low-carbon policies, thus improving our understanding on low-carbon policies, multiple impacts, and CGE models. We also identify the gaps and potential cutting-edge techniques of current low-carbon policy research. Future work should improve the capacity of CGE models to simulate actual ‘second-best’ policies, provide feedback of complex impacts on policy optimization, and enhance dynamic mechanisms on structural change.
Pancreatic cancer (PC) is the most lethal malignancy worldwide due to its delayed diagnosis and limited treatment options. Despite great progress in clinical trials of immunotherapies for various ...cancers, their effectiveness in PC is very low, indicating that immune evasion is still a major obstacle to immunotherapy in PC. However, the mechanism of immune escape in PC is not fully understood, which substantially restricts the development of immunotherapy. As an important component of intercellular communication networks, extracellular vesicles (EVs) have attracted increasing attention in relation to immune escape. This review aims to provide a better understanding of the roles of EVs in tumor immune escape and the potential to expand their application in cancer immunotherapy. The relationship between PC and the tumor immune microenvironment is briefly introduced. Then, the mechanism by which EVs are involved in immune regulation is summarized, and the latest progress in determining the role of EVs in regulating PC immune escape is highlighted.
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SUMMARY
Joint inversion for the same or different geophysical parameters is proved to be an effective technique for obtaining high-resolution solutions. Thus, comprehensive geophysical interpretation ...based on joint inversion has been widely concerned and applied in recent years. To realize joint inversion conveniently and efficiently, we proposed a new inversion strategy based on the alternating direction method of multipliers. In this regard, three optimization algorithms were presented respectively to attain the joint inversion of body wave traveltime and surface wave dispersion data, to obtain the joint inversion of magnetotelluric and seismic data with cross-gradient constraints, and to acquire gravity constrained inversion. A complex model with inconsistent structures in terms of resistivity, velocity and density was designed to evaluate the accuracy and effectiveness of the multiparameter joint inversion algorithms. In our joint inversion processes, each method was optimized independently and the jointly inverted results were significantly more accurate than those of separate inversions. Finally, we applied the algorithms to the field data involving gravity anomaly data, magnetotelluric data and Rayleigh wave dispersion data. The reliable underground structure was achieved by the joint interpretation of density, resistivity and velocity profiles, which verified the practicality of the inversion strategy in the actual data.
Detonation combustion can produce pressure enhancement effect, increasing engine thrust. In this paper, a 2D Euler control equation with chemical reaction is used to solve the periodic flow of the ...detonation wave in a rectangular plane. The combustion of the air-breathing continuous rotating detonation engine is simulated. The RDE thrust is obtained through the outlet parameters of the engine. The fuel used is hydrogen, with the equivalent ratio to air. The calculation reflects the working condition of the engine running at low speed. The operating conditions of the engine at low speed are calculated, with a low intake pressure and temperature of 300K and 0.2/0.35 MPa respectively. It is found that the thermal efficiency of detonation wave is higher than that of the deflagration wave under low inlet pressure and temperature, and the thrust of RDE is significantly higher than that of the deflagration engine. The pressure enhancement effect of RDE is not as strong as that of detonation wave, so the pressure ratio of detonation wave can not be used to calculate the engine efficiency.
Angiogenesis is critical to wound repair due to its role in providing oxygen and nutrients that are required to support the growth and function of reparative cells in damaged tissues. Adenosine ...receptors are claimed to be of paramount importance in driving wound angiogenesis by inducing VEGF. However, the underlying mechanisms for the regulation of adenosine receptors in VEGF as well as eNOS remain poorly understood. In the present study, we found that adenosine and the non-selective adenosine receptor agonists (NECA) induced tube formation in HMEC-1 in a dose-dependent manner. Adenosine or NECA (10 µmol/L) significantly augmented the number and length of the segments in comparison with the control. Simultaneously, VEGF and eNOS were significantly upregulated following the administration of 10 µmol/L NECA, while they were suppressed after A2B AR genetic silencing and pharmacological inhibition by MRS1754. In addition, VEGF expression and eNOS bioavailability elimination significantly reduced the formation of capillary-like structures. Furthermore, the activation of A2B AR by NECA significantly increased the intracellular cAMP levels and concomitant CREB phosphorylation, eventually leading to the production of VEGF in HMEC-1. However, the activated PKA-CREB pathway seemed to be invalidated in the induction of eNOS. Moreover, we found that the elicited PI3K/AKT signaling in response to the induction of NECA assisted in regulating eNOS but failed to impact on VEGF generation. In conclusion, the A2B AR activation-driven angiogenesis via cAMP-PKA-CREB mediated VEGF production and PI3K/AKT-dependent upregulation of eNOS in HMEC-1.
Bladder cancer(BC)is one of the most common urinary system tumors, which characterized by a high incidence. Polyporus polysaccharide is the main active component of polyporus, which is clinically ...used in the treatment of bladder cancer, but the mechanism is not clear. In previous study, we isolated homogeneous polyporus polysaccharide(HPP) with high purity from polyporus. The goal of this study was to assess the polarization of macrophages induced by HPP in the bladder tumor microenvironment and explored its anti-bladder cancer mechanism through BBN bladder cancer rat model and Tumor associated macrophages(TAM). The results suggested that HPP regulates TAM polarization to improve the tumor inflammatory microenvironment, possibly through the NF-κB/NLRP3 signaling pathway. Our results suggested that HPP may be a potential therapeutic agent for bladder tumors.
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