Straw return increases crop grain yields and K-use efficiency under a maize-rice cropping system

Straw return is an effective way to improve crop grain yield and potassium(K)use efficiency by increasing soil K content.However,the effects of straw return on soil K supplying capacity,replacement of K fertilizer,and K-use efficiency under maize(Zea mays L.)–rice(Oryza sativa L.)cropping systems are little studied.A two-year field experiment was conducted to determine the physiological determinants of K-use efficiency under straw return with four K fertilization rates.Sr33(straw returned plus 33%of K fertilizer applied)and Sr67(straw returned plus 67%of K fertilizer applied)increased annual crop yields by 1.5%and 3.2%and increased agronomic K-use efficiency by respectively 2.9 and 1.3-fold on average in the two years,compared with the conventional practice S0K100(no straw returned plus normal amounts of K fertilizer applied).The Sr33 and Sr67 treatments resulted in significantly greater equilibrium K concentration ratios(CR0 K)and specifically exchangeable K(KX)values according to quantity/intensity(Q/I)relationship analyses,indicating improvement of the potential soil K supply capacity.However,the Sr67 better maintained the soil exchangeable K level and K balance.The results suggested that K released from maize and rice straw can replace about half of chemical K fertilizer,depending on the available K content in maize–rice cropping system production.

Weakened humoral immune responses of inactivated SARS-CoV-2 vaccines in patients with solid tumors

Dear Editor Coronavirus disease 19(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),remains a pandemic.Cancer patients have a higher risk of poor outcomes for SARS-CoV-2 infection than the general population[1].Vaccines were shown to effectively prevent SARS-CoV-2 infection,severe disease progression,and mortality.Inactivated SARS-CoV-2 vaccines(BBIBPCorV and CoronaVac)have been approved and widely used in China,with the former shown to be more effective than the latter[2].Hence,there is an urgent need to investigate the safety and humoral immune responses of inactivated vaccines in cancer patients.

Interleukin-25 in sputum as a marker of airway inflammation in children asthma

Dear Editor,Interleukin-25(IL-25,also called IL-17E)is an important IL-17 family member that helps initialize and regulate type 2 immunity,exerting an important influence on the pathogenesis of asthma(Corrigan et al.,2011;Barlow et al.,2012).Furthermore,it plays a vital role in initiating type 2 innate lymphoid cell activation and maintenance(Tong and Li,2018)and inducing Th2-type cytokine-mediated allergic airway eosinophilia(Morita et al.,2015).IL-25 expression increases in patients with asthma in different types of lung cells,including lung structural cells(such as endothelium and airway epithelium),eosinophils,T-cells,and mast cells.Following allergen exposure,cells in the bronchial submucosa increase and secrete or respond to IL-25(Corrigan et al.,2011).Plasma IL-25 levels increase in patients with asthma and correlate with lung function(Cheng et al.,2014).The association between IL-25 cells and pulmonary function indicates that IL-25 could be used to monitor asthma severity.In some mouse models,epithelial IL-25 cytokines are closely related with a range of airway inflammation modalities,including type 2 cytokine production,airway eosinophil inflammation,mucinous epithelial metaplasia,and airway hyperresponsiveness(AHR)(Suzukawa et al.,2012).

控股股东“清仓式”股权质押下的减持动因、路径及后果研究——以印纪传媒为例

控股股东在首发限售股锁定期内“清仓式”质押股权,并在限售股解禁后减持的行为引发了资本市场的广泛关注。本文以印纪娱乐传媒股份有限公司(简称印纪传媒)为例,探讨了控股股东“清仓式”股权质押下的减持动因及路径。研究发现,“清仓式”股权质押下控制权与现金流权的极度偏离,以及业绩承诺下的股价泡沫与未来业绩下滑风险,极易诱发控股股东的利益转移动机,促使其高位减持。在路径方面,“清仓式”股权质押下控股股东可通过协议转让减持、质押状态下协议减持及停牌期间协议减持等路径实现高位减持。以上研究表明,控股股东“清仓式”股权质押下的减持行为很可能是一种利益转移手段。本文可为监管部门识别与防范控股股东侵害中小股东利益的行为提供一定的决策参考与经验借鉴。