Pueraria lobata (Willd.) Ohwi is a medicinal and edible homologous plant with a long history in China. Puerarin, the main component isolated from the root of Pueraria lobata, possesses a wide range ...of pharmacological properties. Daidzein and glucuronides are the main metabolites of puerarin and are excreted in the urine and feces. As active substrates of P-gp, multidrug resistance-associated protein and multiple metabolic enzymes, the pharmacokinetics of puerarin can be influenced by different pathological conditions and drug-drug interactions. Due to the poor water-solubility and liposolubility, the applications of puerarin are limited. So far, only puerarin injections and eye drops are on the market. Recent years, researches on improving the bioavailability of puerarin are developing rapidly, various nanotechnologies and preparation technologies including microemulsions and SMEDDS, dendrimers, nanoparticles and nanocrystals have been researched to improve the bioavailability of puerarin. In order to achieve biocompatibility and desired activity, more effective quality evaluations of nanocarriers are required. In this review, we summarize the pharmacokinetics and drug delivery systems of puerarin up to date.
Due to its special physical properties, diamond is widely applied in the field of mechanical processing. The brazing technology is exploited with strong bonding force between the diamond and ...substrate, which can realize metallurgical and chemical bonding between the filler metals and diamond abrasives. In this paper, series of filler metals and brazing methods for diamond tools are reviewed systematically. Filler metals, brazing processing and reliability may be the all-important factors for diamond tools, physical properties and microstructure evolution of the brazed joints are addressed in detail, the fracture modes and stress distribution issues are considered as the major reliability concern. A systematic review of the latest development of diamond tools brazing is given here, which hopefully may provide a reference for the further investigation and application of brazing technology for diamond tools.
Dingoes are wild canids living in Australia, originating from domestic dogs. They have lived isolated from both the wild and the domestic ancestor, making them a unique model for studying ...feralization. Here, we sequence the genomes of 10 dingoes and 2 New Guinea Singing Dogs. Phylogenetic and demographic analyses show that dingoes originate from dogs in southern East Asia, which migrated via Island Southeast Asia to reach Australia around 8300 years ago, and subsequently diverged into a genetically distinct population. Selection analysis identifies 50 positively selected genes enriched in digestion and metabolism, indicating a diet change during feralization of dingoes. Thirteen of these genes have shifted allele frequencies compared to dogs but not compared to wolves. Functional assays show that an A-to-G mutation in ARHGEF7 decreases the endogenous expression, suggesting behavioral adaptations related to the transitions in environment. Our results indicate that the feralization of the dingo induced positive selection on genomic regions correlated to neurodevelopment, metabolism and reproduction, in adaptation to a wild environment.
Sufficient pore size, appropriate stability, and hierarchical porosity are three prerequisites for open frameworks designed for drug delivery, enzyme immobilization, and catalysis involving large ...molecules. Herein, we report a powerful and general strategy, linker thermolysis, to construct ultrastable hierarchically porous metal–organic frameworks (HP-MOFs) with tunable pore size distribution. Linker instability, usually an undesirable trait of MOFs, was exploited to create mesopores by generating crystal defects throughout a microporous MOF crystal via thermolysis. The crystallinity and stability of HP-MOFs remain after thermolabile linkers are selectively removed from multivariate metal–organic frameworks (MTV-MOFs) through a decarboxylation process. A domain-based linker spatial distribution was found to be critical for creating hierarchical pores inside MTV-MOFs. Furthermore, linker thermolysis promotes the formation of ultrasmall metal oxide nanoparticles immobilized in an open framework that exhibits high catalytic activity for Lewis acid-catalyzed reactions. Most importantly, this work provides fresh insights into the connection between linker apportionment and vacancy distribution, which may shed light on probing the disordered linker apportionment in multivariate systems, a long-standing challenge in the study of MTV-MOFs.
Present study was designed to compared the total flavonoids and polyphenols contents and antibacterial activity of hawthorn extracts with different polarities as well as the underlying antibacterial ...mechanisms. The results showed that among all hawthorn extracts, methanol and ethanol extracts (ME and EE) exhibited high levels of total flavonoids and polyphenols contents, followed by acetone, ethyl acetate, trichloromethane and petroleum ether extracts. ME exhibited the strongest antibacterial activity against tested bacteria, especially Staphylococcus aureus with a 1.25 μg/mL of the minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC). Further analysis revealed that the main phenolic compounds from ME were epicatechin (281.6 mg/100 g DW), procyanidin B2 (243.5 mg/100 g DW), chlorogenic acid (84.2 mg/100 g DW) and quercetin (78.4 mg/100 g DW). The action mechanism of ME against S. aureus could be ascribed to ME damaging cell wall and cell membrane integrity, inhibiting intracellular enzyme activity, increasing reactive oxygen species (ROS), also changing expression of associated genes and then inducing apoptosis of S. aureus. In addition, the antimicrobial activity of ME against S. aureus has also been demonstrated to be efficient in the food matrix (whole milk).
Building operation data are important for monitoring, analysis, modeling, and control of building energy systems. However, missing data is one of the major data quality issues, making data imputation ...techniques become increasingly important. There are two key research gaps for missing sensor data imputation in buildings: the lack of customized and automated imputation methodology, and the difficulty of the validation of data imputation methods. In this paper, a framework is developed to address these two gaps. First, a validation data generation module is developed based on pattern recognition to create a validation dataset to quantify the performance of data imputation methods. Second, a pool of data imputation methods is tested under the validation dataset to find an optimal single imputation method for each sensor, which is termed as an ensemble method. The method can reflect the specific mechanism and randomness of missing data from each sensor. The effectiveness of the framework is demonstrated by 18 sensors from a real campus building. The overall accuracy of data imputation for those sensors improves by 18.2% on average compared with the best single data imputation method.
A triphenylphosphine-modified tetra-nuclear Cu(I) coordinated cluster was constructed for enhanced chemodynamic therapy (CDT) by increasing the number of metal centers. Once inside human bladder ...cancer (T24) cells, a larger amount of copper accumulated compared with the mono-nuclear Cu(I) complex; the additional copper could generate more •OH and then induce more obvious apoptosis
a Fenton-like reaction, thus further increasing the tumor inhibition effect and ultimately improving the CDT efficiency.
In this study, the characteristics of shale gas reservoirs of the lower part of the Keluke Formation in the Shihuigou area were investigated by using thin sections, scanning electron microscopy ...(SEM), and isothermal adsorption, combined with geochemical experimental analysis. Consequently, the controlling factors of the adsorption capability and gas content of the studied shale reservoir are explored. The results show that the shale reservoir space of the Keluke Formation is dominated by pores and fractures. The pores are divided into intergranular pores, intragranular pores, and dissolved pores. The pore volume of medium pores is higher than that of micropores, but the specific surface area of the medium pores is lower than that of micropores. The pore size distribution of medium pores has a feature of single peak, while the distribution of micropores is multipeaked. The results of physical properties and field gas adsorption indicate that the reservoir quality and gas content of the lower part of the Keluke Formation are good. Meanwhile, the total organic content (TOC) has a positive relationship with the methane adsorption. However, the field gas adsorption does not have a clear relationship with TOC and methane adsorption, but a positive correlation with clay mineral content. Therefore, the present study concludes that the natural gas in the shale reservoir of the lower part of the Keluke Formation is predominantly accumulated in form of free gas, and the concentration of free gas is higher than that of the adsorbed gas.
Inverse Hall-Petch relationship of FeNiCrCoCu high-entropy alloy.
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•Construct the nanocrystalline FeNiCrCoCu samples with different grain sizes.•Report the inverse Hall-Petch ...relationship of the high-entropy alloy for the first time.•The critical grain size of the inverse Hall-Petch relationship increases with the increase of temperature.•Dislocations play a significant role in both small and large grain samples during plastic deformation.
Molecular dynamics simulations were carried out to investigate the mechanical properties and the Hall-Petch effect of high-entropy alloy using the interatomic potential for the multi-element FeNiCrCoCu. The transition from mechanical strengthening to softening was observed for the simulated samples with the mean grain size ranging from 28.44 to 5.33 nm. The critical grain size of the inverse Hall-Petch relationship increases with the increase of temperature from 10 K to 600 K. Deformation mechanisms caused by grain boundaries and the dislocation activities are involved in accommodating the system stress in the small grain samples during plastic deformation.
In this work, solution-processed indium oxide (In2O3) thin film transistors (TFTs) were fabricated by a two-step annealing method. The influence of post-metal annealing (PMA) temperatures on the ...electrical performance and stability is studied. With the increase of PMA temperatures, the on-state current and off-state current (Ion/Ioff) ratio is improved and the sub-threshold swing (SS) decreased. Moreover, the stability of In2O3 TFTs is also improved. In all, In2O3 TFT with post-metal annealing temperature of 350°С exhibits the best performance (a threshold voltage of 4.75 V, a mobility of 13.8 cm2/V, an Ion/Ioff ratio of 1.8 × 106, and a SS of 0.76 V/decade). Meanwhile, the stability under temperature stress (TBS) and positive bias stress (PBS) also show a good improvement. It shows that the PMA treatment can effectively suppress the interface trap and bulk trap and result in an obviously improvement of the In2O3 TFTs performance.
For the first time, we fabricate solution-processed TFTs with a two-step annealing method including pre-metal annealing and post-metal annealing. With the post-metal annealing treatment, the interface trap and bulk trap are effectively suppressed. And by this way, the device performance got a clearly improvement especially for the stability. Display omitted
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