Strontium titanate is a model transition metal oxide that exhibits versatile properties of special interest for both fundamental and applied researches. There is evidence that most of the attractive ...properties of SrTiO3 are closely associated with oxygen vacancies. Tuning the kinetics of oxygen vacancies is then highly desired. Here we reported on a dramatic tuning of the electro-migration of oxygen vacancies by visible light illumination. It is found that, through depressing activation energy for vacancy diffusion, light illumination remarkably accelerates oxygen vacancies even at room temperature. This effect provides a feasible approach towards the modulation of the anionic processes. The principle proved here can be extended to other perovskite oxides, finding a wide application in oxide electronics.
•New method was proposed to etch diamond by using titanium powder.•The extent of etch of the diamond increased with the temperature rose.•Titanium carbide was formed on diamond surface and no ...graphitization was observed.•The maximum bonding strength of titanium etched diamond and binder was 59.4 MPa.
This paper proposed a method of etching the diamond surface using titanium powder to strengthen the bonding of diamond with the matrix. The effect of heating temperature on the etching behavior of titanium powder on the diamond surface was investigated. The results showed that as the temperature rose, the extent of etch of the diamonds increased and the specific surface area reached the maximum at 0.31 m2·g−1 at 1000 °C. Furthermore, diamond graphitization was not observed. The maximum bonding strength of the Ti-etched diamond and the binder reached 59.4 MPa, which increased by 56% compared with untreated diamond.
Abstract
Thermal power servo system is a typical servo system, the controller as the main component, its parameters decide the control performance of the servo system, The traditional Z-N PID ...parameter setting method is often unable to achieve the best control performance. The author proposes a particle swarm optimization (PSO) algorithm, which uses the integrated performance index time and error absolute value product integral ITAE as the fitness function and applies it to PID control parameter optimization. The model is built in MATLAB/Simulink for analysis and comparision. The results display that the PSO algorithm is characterized by simple principle, few parameters, easy implementation and fast sensitization speed.
The recent Food and Drug Administration’s approval of monoclonal antibodies targeting immune checkpoint receptors (ICRs) for recurrent or metastatic head and neck squamous cell carcinoma (HNSCC) ...offers exciting promise to improve patient outcome and reduce morbidities. A favorable response to ICR blockade relies on an extensive collection of preexisting tumor-specific T cells in the tumor microenvironment (TME). ICR blockade reinvigorates exhausted CD8+ T cells and enhances immune killing. However, resistance to ICR blockade is observed in about 85% of patients with HNSCC, therefore highlighting the importance of characterizing the mechanisms underlying HNSCC immune escape and exploring combinatorial strategies to sensitize hypoimmunogenic cold HNSCC to ICR inhibition. Cancer vaccines are designed to bypass the cold TME and directly deliver cancer antigens to antigen-presenting cells (APCs); these vaccines epitomize a priming strategy to synergize with ICR inhibitors. Cancer cells are ineffective antigen presenters, and poor APC infiltration as well as the M2-like polarization in the TME further dampens antigen uptake and processing, both of which render ineffective innate and adaptive immune detection. Cancer vaccines directly activate APC and expand the tumor-specific T-cell repertoire. In addition, cancer vaccines often contain an adjuvant, which further improves APC function, promotes epitope spreading, and augments host intrinsic antitumor immunity. Thus, the vaccine-induced immune priming generates a pool of effectors whose function can be enhanced by ICR inhibitors. In this review, we summarize the major HNSCC immune evasion strategies, the ongoing effort toward improving HNSCC vaccines, and the current challenges limiting the efficacy of cancer vaccines.
Aims: To prepare, purify and characterize an extracellular enzyme from Myxococcus fulvus ANSM068, designated as myxobacteria aflatoxin degradation enzyme (MADE), which possesses degradation activity ...against aflatoxin B1 (AFB1), G1 (AFG1) and M1 (AFM1) in solution.
Methods and Results: The culture supernatant of strain M. fulvus demonstrated high degradation ability against AFB1 (71·89%), AFG1 (68·13%) and AFM1 (63·82%) after 48 h of incubation. An enzyme was purified from the supernatant of M. fulvus using ethanol precipitation and chromatography on DEAE‐Sepharose and Superdex 75. An overall 166‐fold purification of the enzyme with a recovery of 57% and a final specific activity of 569·44 × 103 U mg−1 was obtained using the present purification protocol. The apparent molecular mass of MADE was estimated to be 32 kDa by SDS‐PAGE. AFG1 and AFM1 were significantly degraded, by 96·96 and 95·80%, respectively, when treated with pure MADE (100 U ml−1) produced by strain ANSM068. MADE exhibited the largest amount of activity at 35°C and pH 6·0, with Mg2+ ions greatly promoting and Zn2+ strongly inhibiting MADE activity.
Conclusions: An aflatoxin degradation enzyme from bacterial isolates can effectively remove aflatoxin B1, G1 and M1 in solution.
Significance and Impact of the Study: The high activity and wide temperature and pH range of MADE for the degradation of aflatoxin have promising applications in control of mycotoxins during food and feed processing.
•Experimental confirmation of predicted interfacial states of graphene on SiC(0001)•Li intercalation effectively quenches interfacial states•Missing graphene phonon signatures reflect strong elastic ...transport channel
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A low-temperature scanning tunnelling microscope (STM) has been used to study the graphene-SiC(0001) interface before and after Li intercalation. For clean graphene, spectroscopy of the differential conductance corroborates previous theoretical findings for the interfacial electronic structure (M. Kajihara et al., Surf. Sci. 647, 39 (2016)). An unambiguous relation between the spectroscopic onset of the interface states with changes in STM images is presented. Li intercalation leads to the disappearance of the 6 × 6 superstructure of clean graphene on SiC(0001) and efficiently suppresses the interface states. The additional doping of graphene due to the presence of Li is reflected by the shift of the Dirac point further below the Fermi energy.
The rapid growth in coal and oil consumption has led to increasing emissions of greenhouse gases as well as air pollutants in China. In response to this, the Chinese government has begun to formulate ...policies to retard the increasing use of energy consumption and to improve air quality. This paper attempts to quantify the co-benefits of reducing carbon dioxide emissions and improving air quality from policies that are originally formulated to improve energy efficiency and to abate emissions of air pollutants from energy use. The present authors have developed an integrated approach, combining an energy projection model, an emission estimation model, an air quality simulation model, and a health benefit evaluation model, to assess the co-benefits of two different sets of energy policies of China. The modeling results show that significant benefits, including 1469 million tonnes of reduced emissions of CO
2, 12–32% decline in air pollutant concentrations, and more than 100 billion US$ of health benefit, can be achieved around the year 2030 if aggressive energy policies are implemented. The analyses suggest that such energy policies could do a lot of benefit to the environment. Moreover, better industry structure and energy structure is essential for higher air quality.
•A transient VRFB model with anion exchange membrane (AEM) is proposed.•AEM parameters are brought into the description of charge and mass transfer.•Current density in AEM is carried by both H+ and ...HSO4− ions.•Suggestion for optimizing AEM parameters to improve VRFB performance is given.
Vanadium redox flow batteries (VRFBs) with anion exchange membranes (AEMs) exhibit a high columbic efficiency and slow capacity decay due to the reduced crossover rate of vanadium ions. Modeling of this promising type of flow battery is challenging because of the difficulty in the description of charge and mass transfer through AEMs. In this work, we propose a transient model for VRFBs with AEM, which incorporates the ion selective adsorption to overcome the inaccurate description of ion distributions in AEM, and improves the transport coefficients to avoid their changes with different electrolytes, thereby introducing AEM parameters such as porosity and fixed charges into the description of charge and mass transfer. It shows that the simulation results of ion selective adsorption are highly consistent with the experiment; the effects of AEM parameters on transport processes and battery performance are well captured. Interestingly, it is found that the current density in AEM is carried by both H+ and HSO4− ions, and the proportion of H+ ions is quite large. At high current densities, an increase in AEM porosity greatly improve the voltage efficiency while maintaining a high coulombic efficiency. Meanwhile, small capacity decay rate can be obtained by adjusting fixed concentration.
1. The major histocompatibility complex (MHC) is a highly polymorphic region of the genome essential to immune responses and animal health. However, avian MHC genetic structure is different from that ...of mammals. In this study, the structure and expression of Korean quail MHC class I gene was analysed.
2. The quail MHC gene consisted of eight exons and seven introns. The open reading frame of the cDNA was 353 amino acids, and the molecular weight was about 38.91 kDa. Exons 1 and 2 coded for leading peptides and alpha 1 regions, respectively. Exons 3 and 4 encoded alpha 2 and alpha 3 regions. Exons 5 to 8 coded for connecting peptides and transmembrane regions/cytoplasmic regions (TM/CY). The Korean quail MHC class I amino acid sequence shared 87% to 99% homology with Japanese quail and 71% to 75% with chicken. The amino acid shared 40% and 43% homology with humans and mice, respectively.
3. Real-time quantitative PCR showed that MHC-I was highly expressed in immune tissues such as the bursa of Fabricius. Moreover, the constructed evolutionary tree was consistent with accepted evolutionary pathways.
4. MHC-I is closely related to the host's immune system, and these findings may help to better understand the role of Korean quail MHC-I in the immune system.
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