Inactivated H9N2 vaccines developed with early strains do not protect against recent H9N2 viruses:Call for a change in H9N2 control policy

H9N2 virus has been widely distributed in wild birds and poultry around the world since its first emergence in the United States of America in 1966(Gu et al.2017;Carnaccini and Perez 2020).The virus appeared in chickens in China in the early 1990s,and over the last two decades has gradually become the dominant epidemic subtype(Sun and Liu 2015;Bi et al.2020).Although H9N2 virus infection alone cannot cause severe disease or death in poultry,H9N2 virus-infected birds experience a degree of egg production drop and can be easily infected by other pathogens,thus causing economic losses for poultry industry.

In-situ decoration of metallic Bi on BiOBr with exposed(110)facets and surface oxygen vacancy for enhanced solar light photocatalytic degradation of gaseous n-hexane

Photocatalytic degradation of gaseous pollutants on Bi-based semiconductors under solar lightirradiation has attracted significant attention.However,their application in gaseous straight-chainalkane purification is still rare.Here,a series of Bi/BiOBr composites were solvothermally synthe-sized and applied in solar-light-driven photocatalytic degradation of gaseous n-hexane.The charac-terization results revealed that both increasing number of functional groups of alcohol solvent(from methanol and ethylene glycol to glycerol)and solvothermal temperature(from 160 and 180to 200℃)facilitated the in-situ formation of metallic Bi nanospheres on BiOBr nanoplates withexposed(110)facets.Meanwhile,chemical bonding between Bi and BiOBr was observed on theseexposed facets that resulted in the formation of surface oxygen vacancy.Furthermore,the synergis-tic effect of optimum surface oxygen vacancy on exposed(110)facets led to a high visible light re-sponse,narrow band gap,great photocurrent,low recombination rate of the charge carriers,andstrong·O2-and h*formation,all of which resulted in the highest removal efficiency of 97.4%within120 min of 15 ppmv of n-hexane on Bi/BiOBr.Our findings efficiently broaden the application ofBi-based photocatalysis technology in the purification of gaseous straight-chain pollutants emittedby the petrochemical industry.

Development Path of Innovation and Entrepreneurship Education in Universities Under the Digital Economy

With the development of digital technology and new models of digital economy,innovation and entrepreneurship education in colleges and universities is facing a new development situation.New methods such as online courses,digital platforms,and value co-creation have brought new opportunities and challenges to the content,mode,and mechanism of innovation and entrepreneurship education.This paper discusses the content and new opportunities of digital entrepreneurship,analyzes the differences between traditional entrepreneurship and digital entrepreneurship,and puts forward the strategy path of entrepreneurship education under the digital economy.

Taurocholic acid inhibits the response to interferon-αtherapy in patients with HBeAg-positive chronic hepatitis B by impairing CD8^(+)T and NK cell function

Pegylated interferon-alpha (PegIFNα) therapy has limited effectiveness in hepatitis B e-antigen (HBeAg)-positive chronic hepatitis B (CHB) patients. However, the mechanism underlying this failure is poorly understood. We aimed to investigate the influence of bile acids (BAs), especially taurocholic acid (TCA), on the response to PegIFNα therapy in CHB patients. Here, we used mass spectrometry to determine serum BA profiles in 110 patients with chronic HBV infection and 20 healthy controls (HCs). We found that serum BAs, especially TCA, were significantly elevated in HBeAg-positive CHB patients compared with those in HCs and patients in other phases of chronic HBV infection. Moreover, serum BAs, particularly TCA, inhibited the response to PegIFNα therapy in HBeAg-positive CHB patients. Mechanistically, the expression levels of IFN-γ, TNF-α, granzyme B, and perforin were measured using flow cytometry to assess the effector functions of immune cells in patients with low or high BA levels. We found that BAs reduced the number and proportion and impaired the effector functions of CD3^(+)CD8^(+) T cells and natural killer (NK) cells in HBeAg-positive CHB patients. TCA in particular reduced the frequency and impaired the effector functions of CD3^(+)CD8^(+) T and NK cells in vitro and in vivo and inhibited the immunoregulatory activity of IFN-α in vitro. Thus, our results show that BAs, especially TCA, inhibit the response to PegIFNα therapy by impairing the effector functions of CD3^(+)CD8^(+) T and NK cells in HBeAg-positive CHB patients. Our findings suggest that targeting TCA could be a promising approach for restoring IFN-α responsiveness during CHB treatment.

Fast screening compositions of PM2.5 by ATR-FTIR： Comparison with results from IC and OC/EC analyzers

Chemical speciation of fine particles or PM2.5 collected on filters is still a cosily and time- consuming task. In this study, filter-based PM2.5 samples were collected during November-December 2013 at four sites in Guangzhou, and the major components were fast screened （~ 7 rain per filter sample） by Attenuated Total Reflectance （ATR）-Fourier Transform Infrared Spectroscopic （FTIR） in comparison with that measured by Organic carbon/Element carbon （OC/ EC） analyzer and Ion Chromatography （IC）. The concentrations of nitrate, ammonium, sulfate, primary organic carbon （POC） and secondary organic carbon （SOC） measured by OC/EC and IC analyzers were better correlated with their infrared absorption peak heights at 1320 cm 1 for nitrate, 1435, 3045 and 3215 cm^-1 for ammonium, 615 cm^-1 for sulfate, 690, 760 and 890 cm^-1 for POC and 1640 and 1660 cm^-1 for SOC respectively, during polluted days （PM2.5 〉 75 μg/m^3） than during clean days （PM2.5〈 75 μg/m^3）. With the evolution of a haze episode during our field campaign, the concentrations of the major PM2.5 components displayed consistent variations with their infrared absorption peak heights, suggesting ATR-FTIR could be a fast and useful technique to characterize filter-based PM2.5 compositions particularly during pollution events although cautions should be taken when PM2.5 levels are low. Notably, elevated PM2.5 mass concentrations occurred with enhanced ratios of [NO^-3][SO^2-4] and [NH^＋4]/[SO^2-4], implying that nitrogenous components play vital roles in the PM2.5 pollution events in the study region.

Changes in visibility with PM_(2.5) composition and relative humidity at a background site in the Pearl River Delta region

In fall–winter, 2007–2013, visibility and light scattering coefficients（b sp） were measured along with PM_（2.5）mass concentrations and chemical compositions at a background site in the Pearl River Delta（PRD） region. The daily average visibility increased significantly（p 〈 0.01） at a rate of 1.1 km/year, yet its median stabilized at ~13 km. No haze days occurred when the 24-hr mean PM_（2.5）mass concentration was below 75 μg/m^3. By multiple linear regression on the chemical budget of particle scattering coefficient（b sp）, we obtained site-specific mass scattering efficiency（MSE） values of 6.5 ± 0.2, 2.6 ± 0.3, 2.4 ± 0.7 and 7.3 ± 1.2 m2/g,respectively, for organic matter（OM）, ammonium sulfate（AS）, ammonium nitrate（AN） and sea salt（SS）. The reconstructed light extinction coefficient（b ext） based on the Interagency Monitoring of Protected Visual Environments（IMPROVE） algorithm with our site-specific MSE revealed that OM, AS, AN, SS and light-absorbing carbon（LAC） on average contributed 45.9% ± 1.6%,25.6% ± 1.2%, 12.0% ± 0.7%, 11.2% ± 0.9% and 5.4% ± 0.3% to light extinction, respectively.Averaged b ext displayed a significant reduction rate of 14.1/Mm·year（p 〈 0.05）; this rate would be 82% higher if it were not counteracted by increasing relative humidity（RH） and hygroscopic growth factor（f（RH）） at rates of 2.5% and 0.16/year-1（p 〈 0.01）, respectively, during the fall–winter, 2007–2013. This growth of RH and f（RH） partly offsets the positive effects of lowered AS in improving visibility, and aggravated the negative effects of increasing AN to impair visibility.

Manganese silicate nanospheres-incorporated hydrogels:starvation therapy and tissue regeneration

To prevent postoperative skin tumor recurrence and repair skin wound,a glucose oxidase(GOx)-loaded manganese silicate hollow nanospheres(MS HNSs)-incorporated alginate hydrogel(G/MS-SA)was constructed for starvation-photothermal therapy and skin tissue regeneration.The MS HNSs showed a photothermal conversion efficiency of 38.5%,and endowed composite hydrogels with satisfactory photothermal effect.Taking advantage of the catalytic activity of Mn ions,the composite hydrogels could decompose hydrogen peroxide(H2O2)into oxygen(O2),which can alleviate the problem of tumor hypoxia microenvironment and endow GOx with an ability to consume glucose in the presence of O2 for tumor starvation.Meanwhile,hyperthermia triggered by near infrared(NIR)irradiation could not only accelerate the reaction rate of H2O2 decomposition by MS HNSs and glucose consumption by GOx,but also ablate tumor cells.The anti-tumor results showed that synergistic effect of starvation-photothermal therapy led to the highest death rate of tumor cells among all groups,and its anti-tumor effect was obviously improved as compared with that of single photothermal treatment or starvation treatment.Interestingly,the introduction of MS HNSs into hydrogels could distinctly promote the epithelialization of the wound beds by releasing Mn ions as compared with the hydrogels without MS HNSs.It is expected that such a multifunctional platform with starvation-photothermal therapy will be promising for treating tumor-caused skin defects in combination of its regeneration bioactivity in the future.

Three-Dimensional Sulfated Bacterial Cellulose/Gelatin Composite Scaffolds for Culturing Hepatocytes

The liver is the hub of human metabolism and involves many diseases.To better work on the mechanism and treatment of liver diseases,it is of particular interest to design 3-dimensional scaffolds suitable for culturing hepatocytes in vitro to simulate their metabolic and regenerative abilities.In this study,sulfated bacterial cellulose(SBC)was prepared as the building block of cell scaffolds,motivated by the anionic nature and 3-dimensional structure of hepatic extracellular matrix,and its reaction condition for sulfate esterification was optimized by changing the reaction time.The analysis and study of the microscopic morphology,structure,and cytocompatibility of SBCs showed that they possess good biocompatibility and meet the requirements for tissue engineering.Next,SBC was mixed with gelatin for composite scaffolds(SBC/Gel)for culturing hepatocytes by homogenization and freeze-drying methods,whose physical properties such as pore size,porosity,and compression properties were compared with gelatin(Gel)scaffolds as the control group,and the cytological activity and hemocompatibility of the composite scaffolds were investigated.The results showed that the SBC/Gel composite has better porosity and compression properties,as well as good cytocompatibility and hemocompatibility,and could be applied to 3-dimensional culture of hepatocytes for drug screening or liver tissue engineering.