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B12C4 systems achieve better 6Li enrichment in the organic phase and B15C5 systems achieve better 7Li enrichment in the aqueous phase.

The Moringa oleifera Lam. leaf addition on FBT for the co-fermentation could increase volatile compounds contents, improve sensory properties and enhance its health benefits.

Spacecraft work beyond the earth’s atmosphere. With the development of aerospace industry, missions of spacecrafts are becoming more and more complex. So spacecrafts need more efficient and accurate navigation system to help their works. Every navigation system has its advantages and disadvantages. This paper summarizes several common navigation methods and their characteristics, and the application of different navigation methods, as well as their trend of future development.

Two neutral polysaccharides (PPP1-1 and PPP1-2) were purified from persimmon peel. PPP1-1 (21.84 kDa) was mainly composed of arabinose (22.92 %), galactose (21.09 %), glucose (35.13 %), and xylose (19.09 %), while PPP1-2 (10.42 kDa) mainly contained arabinose (32.98 %), galactose (20.81 %), glucose (26.86 %), xylose (10.46 %), and mannose (7.63 %). Methylation and NMR spectra analysis demonstrated that the backbone of PPP1-1 appeared to be →6)-α-D-Glcp-(1→, →2,6)-α-D-Glcp-(1→, →5)-α-L-Araf-(1→, and →3,5)-α-L-Araf-(1 → residues with branches consisting of →3)-α-L-Araf-(1→, →4)-α-D-Glcp-(1→, →3)-β-D-Galp-(1→, →4)-β-D-Galp-(1→, →4)-β-D-Xylp-(1→, →6)-β-D-Galp-(1→, →4)-β-D-Manp-(1→, and α-L-Araf-(1 → residues. The main chain of PPP1-2 was composed of →6)-α-D-Glcp-(1→, →5)-α-L-Araf-(1→, and →3,5)-α-L-Araf-(1 → residues with branches consisting of →3)-α-L-Araf-(1→, →1,2)-α-D-Glcp-(6→, →4)-α-D-Glcp-(1→, →3)-β-D-Galp-(1→, →4)-β-D-Galp-(1→, →6)-β-D-Galp-(1→, →4)-β-D-Xylp-(1→, →4,6)-α-D-Glcp-(1→, and →4)-β-D-Manp-(1 → residues and terminal of α-L-Araf-(1 → residue. PPP1-2 exhibited stronger antioxidant activities and better thermal stability than PPP1-1. Our results provided the foundation for further investigating the structure and biological activities of persimmon peel polysaccharides and highlighted their potential to become potential antioxidants in functional food.

BaF2 submicron spherical particles, formed by the self-assembly of nanocubes, were prepared by a low-temperature hydrothermal method with the aid of EDTA-2Na.

Micro electroforming has become one of the key technologies for metal micro devices fabrication. However, residual stress in electroformed layer of micro devices will reduce their dimensional accuracy and service life. Affected by residual stresse, there is serious bending deformation occurred in cantilevered micro structure during electroforming process. In this paper, megasonic agitation method was employed to obtain low stress in the cantilevered micro structure firstly. Then, the cantilevered micro structures electroformed with and without megasonic were tested by nanoindentation method. The difference of Suresh model and Lee model on the stress calculation results was discussed. By contrast with X-ray diffraction (XRD) method, the calculation results obtained by Lee model in nanoindentation testing are closer to the actual residual stress of the nickel electroformed layer. The nanoindentation testing results obtained by Lee model show that the mean compressive stress of micro structures electroformed with megasonic has a decrease of 57.84 % compared with that without megasonic. The research results indicated that megasonic agitation method is a low residual stress fabrication technique in micro electroforming process. Besides, nanoindentation is a feasible method to measure the residual stress of metal micro structure, due to its excellent properties of high spatial resolution and wide application range.

SUMO-specific proteases (SENPs) play pivotal roles in maintaining the balance of SUMOylation/de-SUMOylation and in SUMO recycling. Deregulation of SENPs leads to cellular dysfunction and corresponding diseases. As a key member of the SENP family, SENP1 is highly correlated with various cancers. However, the potential role of SENP1 in leukemia, especially in acute lymphoblastic leukemia (ALL), is not clear. This study shows that ALL cells knocking down SENP1 display compromised growth rather than significant alterations in chemosensitivity, although ALL relapse samples have a relatively higher expression of SENP1 than the paired diagnosis samples. Camptothecin derivatives 7-ethylcamptothecin (7E-CPT, a monomer compound) and topotecan (TPT, an approved clinical drug) induce specific SENP1 reduction and severe apoptosis of ALL cells, showing strong anticancer effects against ALL. Conversely, SENP1 could attenuate this inhibitory effect by targeting DNA topoisomerase I (TOP1) for de-SUMOylation, indicating that specific reduction in SENP1 induced by 7E-CPT and/or topotecan inhibits the proliferation of ALL cells.

Gut microbiota dysbiosis could aggravate the development of ulcerative colitis (UC).

With the increase in unhealthy lifestyles, obesity is increasingly common, which could cause many metabolic diseases. In recent research, natural product extracts have shown tremendous potential antiobesity effects via different mechanisms. In this review, we focused on widely adopted extraction methods, bioactive ingredients types, and antiobesity mechanisms of natural product extracts in the recent reports. The extraction methods include solid-liquid extraction, microwave-assisted extractions, and supercritical fluid extraction. Moreover, the bioactive ingredients identified in natural product extracts are phenolic compounds, oligosaccharides, polysaccharides, and terpenoids. These exert antiobesity effects through multiple mechanisms, including suppressing the appetite, increasing energy expenditure, inhibiting enzyme activity, modulating lipid homeostasis and adipocyte lifecycle, reducing oxidative and inflammation, and improving intestinal bacteria. However, the antiobesity effects of natural products require further evaluation. Furthermore, the improvement of the bioavailability and effective and safe human dose of these bioactive ingredients should be the focus of future work.

UBR5, a HECT-domain E3 ubiquitin ligase, is an attractive therapeutic target for aggressive breast cancers. Defining the substrates of UBR5 is crucial for scientific understanding and clinical intervention. Here, we demonstrate that CDC73, a component of the RNA polymerase II-associated factor 1 complex, is a key substrate that impedes UBR5’s profound tumorigenic and metastatic activities in triple-negative breast cancer (TNBC) via mechanisms of regulating the expression of β-catenin and E-cadherin, tumor cell apoptosis and CD8+ T cell infiltration. Expression of CDC73 is also negatively associated with the progression of breast cancer patients. Moreover, we show that UBR5 destabilizes CDC73 by polyubiquitination at Lys243, Lys247, and Lys257 in a non-canonical manner that is dependent on the non-phosphorylation state of CDC73 at Ser465. CDC73 could serve as a molecular switch to modulate UBR5’s pro-tumor activities and may provide a potential approach to developing breast cancer therapeutic interventions.

Companilactobacillus crustorum MN047-derived bacteriocins (CCDB) have inhibitory effects on the growth of pathogens. In this study, a pectin/zein beads delivery system was used to investigate the effects of CCDB on the dextran sulfate sodium-induced colitis in mice. The focus was given on aspects linked with the gut microbiota, intestinal epithelial barrier, oxidative stress, and inflammation. Results suggested that CCDB alleviated the pathological symptoms of colitis, including increased disease activity index and shortened colon length. CCDB strengthened the gut barrier by increasing goblet cells and promoting the expressions of MUC2 and tight junctions-related proteins. CCDB decreased oxidative mediators and increased antioxidant mediators in serum or colon tissue. Furthermore, CCDB reduced harmful bacteria and enriched beneficial bacteria, which further decreased serum LPS and increased fecal butyric acid. In addition, CCDB inhibited the overexpressions of proinflammatory cytokines, chemokines, and pathogens/LPS-activated TLR4/NF-κB pathway. Therefore, CCDB is a potential dietary supplement to relieve colitis.

Three-dimensional carbon-based porous materials have proven to be quite useful for tailoring material properties in the energy conservation and environmental protection applications. In view of the three-dimensional and well-defined structure of metal-organic frameworks (MOFs), a novel carbon-based magnetic porous material (HKUST-Fe3O4) has been designed and constructed by MOF-guest interactions of high-temperature pyrolysis. The obtained HKUST-Fe3O4 exhibited the unique features of superparamagnetism, a macro/mesoporous structure, environmental protection (inexistence of toxic heavy metal ions), and physicochemical stability and has shown high adsorption capacity and rapid adsorption for carcinogenic organic pollutants (for example, rhodamine B) with an environmentally friendly character and excellent reusability. We demonstrate that the unique/superior advantages of HKUST-Fe3O4 could meet the requirements of environment cleaning, especially for removing the targeted organic pollutant from water. Moreover, the specific HKUST-Fe3O4 and organic pollutant interaction mechanism has been analyzed in detail via parameter-free calculations. This study proposes a promising strategy for constructing novel carbon-based magnetic nanomaterials for various applications, not limitated to pollutant removal.

Three-dimensional porous carbon-based materials from metal–organic frameworks (MOFs) have been proven useful in structural mechanical and catalytic applications due to the high specific surface area and excellent electron transport property. However, introducing and loading of metal catalytic sites on MOF-derived porous carbon-based materials always involves complex multistep synthetic processes and unwarrantable catalyst sites with high catalytic activity. Here, we have developed a facile Mo-doping-assisted strategy to construct a highly active nanorod with Ni-based catalyst nanoparticles from a MOF (MCF-61). Thanks to the assistance of Mo-doping to restrain the migration and aggregation of elemental Ni, the obtained Mo-doped Ni-based catalyst (MNC) exhibited excellent catalytic activity in the solution-phase hydrogenation of nitrophenols compared to those reported in other studies. Moreover, the role of molecular structures of nitrophenols on their reduction in MNC has been revealed by quantum chemical ...

Efficient Market Hypothesis has always been a hot topic for empirical study in Finance. In this paper, we examine the efficiencies of Mainland China and Hong Kong markets by analyzing the different reactions of stock price and volatility to credit rating changes. The study of impact of credit rating change also fills a gap of no empirical analysis of credit rating change effect in these two markets. In a semi-strong efficient market, investors cannot make profit based on public information. In this study, we select Chinese cross-listed A-H share companies as our sample and compare the effects of bond rating changes on A-share stock price and H-share stock price. The differences in the stock return and volatility reactions signify the differences in market efficiency. The results from an event study indicate that neither market is semi-strong efficient and Hong Kong market is more efficient in digesting credit rating change information. Both Mainland China and Hong Kong markets show statistically significant and negative abnormal returns after the announcement of credit rating downgrades and only Mainland China market shows statistically significant abnormal returns before the announcement. Hong Kong market shows statistically significant and positive abnormal returns around the announcement of credit rating upgrades and Mainland China market shows no statistically significant abnormal returns around the announcement. Concerning volatility, credit rating downgrades can cause significant positive abnormal volatility around the announcement date in both Mainland China and Hong Kong markets, while there is no significant abnormal volatility around the announcement of credit rating upgrades. In the cross-sectional analysis of return reactions to credit rating changes, pre-announcement abnormal returns and whether credit ratings moved to speculative grade have an impact on the abnormal returns during the announcement.

In order to solve the problems of long time consuming and easy failure of the existing coarse registration algorithms based on global registration on two 3D point clouds with low overlap rate, we proposed a coarse registration algorithm based on feature regions and the Super 4-Points Congruent Sets (SUPER4PCS) algorithm. Firstly, intrinsic shape signatures (ISS) algorithm was used to extract and describe the features of the down-sampled point clouds. Secondly, the feature point clouds were divided into regions and the initial overlapped sub-regions were extracted. Thirdly, the complete overlapping regions were grown from the overlapped sub-regions and gradually recovered. Finally, the SUPER4PCS was used for registration on the complete overlapping regions. The experimental results showed that the geometric accuracy, registration success rate, and robustness of the proposed algorithm were better than that of SUPER4PCS and its improved algorithms, and the time consumption was one order of magnitude lower than that of SUPER4PCS on point clouds with low overlap rate.

In this study, the mechanism behind the effect of hydrostatic pressure on phosphorus solubilization from sediment to water was studied in culture experiments using reactors pressurized at 0.1, 0.2, 0.5, and 1.0 MPa. In the sterilized group, the phosphorus content in the sediment was not affected by the hydrostatic pressure. In the unsterilized group, the phosphorus release values were 162, 198, 253, and 289 mg kg−1 at 0.1, 0.2, 0.5, and 1.0 MPa, respectively. In addition, when the hydrostatic pressure was increased from 0.1 to 1 MPa, the activity of alkaline phosphatase increased from 210 to 357 mg kg−1 h−1. The abundance of inorganic phosphorus-solubilizing bacteria increased with rising hydrostatic pressure, but the abundance of organic phosphorus-solubilizing bacteria was highest when the hydrostatic pressure was 0.5 MPa. Pearson regression analysis indicated that the maximum organic phosphorus-solubilizing capacity was positively correlated with the alkaline phosphatase activity (R = 0.97, p

Through-mask electrochemical etching (TMEE) is one of the main methods to fabricate metal microstructures array in large scale. In deep metal microstructure etching process, lateral corrosion problem seriously affects the etching localization. In this paper, megasonic and particle combined through mask electrochemical etching (MP-TMEE) method was proposed to improve the etching localization in TMEE process. Experimental results show that the etching factor (EF) was greatly improved by MP-TMEE method compared to traditional TMEE. With the use of MP-TMEE, when the feature size of the mask was 100 μm, the average diameter and depth of the etched micro pits were 148.7 μm and 59.9 μm. The use of MP-TMEE instead of TMEE leads to an increase in EF from 1.58 to 2.50. Besides, the mechanism of the synergistic effect of megasonic and the particles in MP-TMEE process was investigated. An erosion theoretical model of passivation film was established and verified by electrochemical impedance spectroscopy (EIS) method. The measurement results of EIS show that the micro pit depth and the passivation film resistance have the opposite variation trend, and the passivation film resistance measurement results are consistent with the trend of the theoretical model. Finally, microstructure arrays involving stainless steel micro pit array and micro pillar array, copper micro pit array and micro pillar array were fabricated using MP-TMEE method.

Computer simulation accelerates the selection and application of new electrode materials. The First-principles calculations based on density functional theory (DFT) are performed to evaluate the performance as cathode for Potassium ion batteries (PIBs) on the structure, electronic conductivity and ionic diffusion of O-doped KMnF3. After taking comprehensive consideration of the calculation results, the nanostructured O-doped KMnF3 was synthesized and the structure and electrochemical properties were further improved by carbon coating. Here, we report a new etch pathway to create a new class of carbon-coated perovskite fluoride to improve the performance of PIB in terms of rate capability and cycle stability. These new material design concepts will help discover and synthesize new materials for PIBs.

Based on lithography and electrochemical deposition technology, an integrative fabrication method of micro RF coaxial transmitter on copper substrates combining positive and negative photoresist processes is proposed in this paper. In this method, positive photoresist (AZ50XT) was used for fabricating sacrificial layer which worked as master mold for electroforming copper; negative photoresist (SU-8) was used for fabricating insulating layer. However, due to the distribution of light intensity inside the AZ50XT photoresist is uneven during the lithography process, which will cause the sidewall of the film tilted. Thus, a method of multiple exposures and developments was proposed to improve the sidewall inclination of the AZ50XT photoresist and provide an accurate master mold for electrochemical deposition of the structure. Meanwhile, contrast experiments were conducted to verify the practical effect. The experiments results show that when the thickness of AZ50XT film is 65 μm, the sidewall inclination can be increased from 67.4° to 84.5°. In addition, the soft-bake parameter was adjusted to further improve the sidewall inclination of AZ50XT film. Ultimately, based on the experimental results, a micro RF coaxial transmitter was fabricated. The outline size of the coaxial transmitter is 3000 μm × 400 μm × 200 μm.

Through-mask electrochemical micromachining (TMEMM) is the primary method to fabricate micro pits with controlled size, location, and density. In order to improve the machining localization and deep etching capability in TMEMM process, a novel method which combined megasonic vibration to TMEMM process is presented in this paper. Firstly, the coupling relationship between sound field, gas-liquid two-phase flow field and electrolytic process was theoretically analyzed. Theoretical analysis results indicate that acoustic wave agitation can promote the electrolytic process by increasing the conductivity of the electrolyte. Based on this theory, a numerical simulation method was used to predict anodic profiles under different megasonic intensity. The simulation results show that the addition of megasonic agitation can obviously improve the machining localization and deep etching capability in TMEMM process. Etching depth of the micro pit increased from 48.22 μm to 77.98 μm with megasonic agitation compared to the without megasonic one. Depth-diameter ratio of the micro pit increased from 0.30 to 0.45. Meanwhile, the etching factor (EF) increased from 1.55 to 2.10. Then, a megasonic electrolyser at 1 MHz was set up, micro pits were etched under different megasionc intensity. The experiment results show that megasonic assisted through-mask electrochemical micromachining (MA-TMEMM) had best process performance when it worked with the increase of megasionc intensity. When the megasonic intensity was 8 W/cm2, micro pits with average diameter of 167.77 μm and 79.62 μm in depth were successfully fabricated. The average depth-diameter ratio of the micro pits was as high as 0.47, and the EF was as high as 2.35. The working mechanism of megasonic in MA-TMEMM process was analyzed too.

Micropillar array is widely used in bionics, thermodynamics and biomedicine because of its advantages in improving surface tribological properties and enhancing heat transfer [1, 2]. Through-mask electrochemical etching is one of the main methods to fabricate metal micropillar array in large scale [3]. In this study, we studied the etching effect of micropillar array with the method of megasonic assisted through-mask electrochemical etching. An anode vibrating type megasonic source at 1MHz was set up. Micropillar arrays were etched at megasionc intensity of 2W/cm^2. Fig. 1(a) shows the fabrication process of the micropillar array. The mask is prepared by photolithography. During the etching process, anode acts as an acoustic source and radiates megasonic waves simultaneously. Fig. 1(b) shows the micropillar arrays which were etched without megasonic and with megasonic agitation. Uniform micropillars were achieved with megasonic agitation compared to without megasonic agitation. Fig. 1(c) and Fig. 1(d) shows the measured height and diameter of the micropillars. Higher micro columns were obtained with megasonic agitation when the diameters of the micro columns are almost identical. Micropillars with an average diameter of 116.95μm and an average height of 11.31μm were obtained with megasonic agitation. Fig. 1(e) shows the etching factor of the micropillars. Average etching factor of the micropillars etched without megasonic agitation and with megasonic are 2.07 and 2.87, respectively. The method of megasonic assisted through-mask electrochemical etching can achieve much higher etching factor than without megasonic agitation. This work opens new promising fields for development of extensive fabrication methods of micropillar array. Reference [1] R. Xiao, R. Enright, E. N. Wang. Langmuir, 26(19) 15070-15075 (2010) [2] M. Shojaeian, A. Koşar. Exp. Thermal Fluid Sci., 63 45-73 (2015) [3] T. Baldhoff, V. Nock, A. T. Marshall, J. Electrochem. Soc., 165 (16) E841-E855 (2018) Figure 1

Five hydroxystilbene derivatives were synthesized and their structures were determined using high-resolution mass spectrometry, 1 H NMR, and IR. In this study, the antioxidant activities of eight hydroxystilbenes(five synthesized hydroxystilbene derivatives and three other compounds) were evaluated with the free radical scavenging model 1, 1-diphenyl-2-picrylhydrazyl. It was observed that there exists a very significant linear relationship between the reciprocal of the EC 50 , value of each of the compounds and the maximum wavelength of the ultraviolet absorption peaks. It is believed that this result will be helpful for the further synthesis of such antioxidants.

Estrogen deficiency is associated with increased incidence of cardiovascular diseases. But merely estrogen supplementary treatment can induce many severe complications such as breast cancer. The present study was designed to elucidate molecular mechanisms underlying increased susceptibility of arrhythmogenesis during myocardial infarction with estrogen deprivation, which provides us a new target to cure cardiac disease accompanied with estrogen deprivation. We successfully established a rat model of myocardial ischemia (MI) accompanied with estrogen deprivation by coronary artery ligation and ovariectomy (OVX). Vulnerability and mortality of ventricular arrhythmias increased in estrogen deficiency rats compared to non estrogen deficiency rats when suffered MI, which was associated with down-regulation of microRNA-151-5p (miR-151-5p). Luciferase Reporter Assay demonstrated that miR-151-5p can bind to the 3'-UTR of FXYD1 (coding gene of phospholemman, PLM) and inhibit its expression. We found that the expression of PLM was increased in (OVX+MI) group compared with MI group. More changes such as down-regulation of Kir2.1/IK1, calcium overload had emerged in (OVX+MI) group compared to MI group merely. Transfection of miR-151-5p into primary cultured myocytes decreased PLM levels and [Ca(2+)]i, however, increased Kir2.1 levels. These effects were abolished by the antisense oligonucleotides against miR-151-5p. Co-immunoprecipitation and immunofluorescent experiments confirmed the co-localization between Kir2.1 and PLM in rat ventricular tissue. We conclude that the increased ventricular arrhythmias vulnerability in response to acute myocardial ischemia in rat is critically dependent upon down-regulation of miR-151-5p. These findings support the proposal that miR-151-5p could be a potential therapeutic target for the prevention of ischemic arrhythmias in the subjects with estrogen deficiency.