Doping of group IVB elements for nickel-rich cobalt-free cathodes

Hetero-element doping is a promising strategy to improve the cycling stability of nickel-rich cobalt-free cathodes for the next-generation high energy-density Li ion batteries.To make doping effective,it is important to understand the mechanism of how the dopants regulate the electronic band,lattice parameter adjusting,or hetero-phase formation to achieve high stability.In this study,we investigate LiNi_(0.9)Mn_(0.1)O_(2)cathodes doped with IVB grouping elements via multiple characterization techniques.By utilizing in situ XRD and TEM methods,we found that the stronger Ti-O bond effectively improves the cathode stability via a dual protection mechanism.Specifically,the bulk lattice of cathode is wellpreserved during cycling as a result of the suppressed H_(2)-H_(3)phase transition,while a in situ formed Ti-rich surface layer can prevent continuous surface degradation.As a result,the 5%Ti doped LiNi_(0.9)Mn_(0.1)O_(2)cathode exhibits a high capacity retention of 96%after 100 cycles.Whereas,despite IVB group elements Zr and Hf have stronger bonding energy with oxygen,their larger ionic radii actually impede their diffusion into the cathode,thereby they can not improve the cycling stability.Our findings uncover the functional origin of doped elements with their dynamic modification on cathode structure,providing mechanistic insights into the design of nickel-rich cobalt-free cathodes.

Federated learning privacy incentives:Reverse auctions and negotiations

The incentive mechanism of federated learning has been a hot topic,but little research has been done on the compensation of privacy loss.To this end,this study uses the Local SGD federal learning framework and gives a theoretical analysis under the use of differential privacy protection.Based on the analysis,a multi‐attribute reverse auction model is proposed to be used for user selection as well as payment calculation for participation in federal learning.The model uses a mixture of economic and non‐economic attributes in making choices for users and is transformed into an optimisation equation to solve the user choice problem.In addition,a post‐auction negotiation model that uses the Rubinstein bargaining model as well as optimisation equations to describe the negotiation process and theoretically demonstrate the improvement of social welfare is proposed.In the experimental part,the authors find that their algorithm improves both the model accuracy and the F1‐score values relative to the comparison algorithms to varying degrees.

A federated learning scheme meets dynamic differential privacy

Federated learning is a widely used distributed learning approach in recent years,however,despite model training from collecting data become to gathering parameters,privacy violations may occur when publishing and sharing models.A dynamic approach is pro-posed to add Gaussian noise more effectively and apply differential privacy to federal deep learning.Concretely,it is abandoning the traditional way of equally distributing the privacy budget e and adjusting the privacy budget to accommodate gradient descent federation learning dynamically,where the parameters depend on computation derived to avoid the impact on the algorithm that hyperparameters are created manually.It also incorporates adaptive threshold cropping to control the sensitivity,and finally,moments accountant is used to counting the∈consumed on the privacy‐preserving,and learning is stopped only if the∈_(total)by clients setting is reached,this allows the privacy budget to be adequately explored for model training.The experimental results on real datasets show that the method training has almost the same effect as the model learning of non‐privacy,which is significantly better than the differential privacy method used by TensorFlow.

Efficacy and safety of anlotinib plus S-1as thirdly-line or later-line treatmentin advanced non-small cell lung cancer

Objective Anlotinib,an oral vascular endothelial growth factor receptor 2(VEGFR2)inhibitor,has confirmed antitumor activity in lung cancer in both in vitro and in vivo assays,and has been recommended as third-line treatment agent in non-oncogene driven non-small cell lung cancer(NSCLC).This prospective study aimed to investigate the efficacy and safety of anlotinib plus S-1 for third-or later-line treatment in patients with advanced NSCLC.Methods Patients with histologically or cytologically confirmed NSCLC,and documented disease progression following second-line chemotherapy,and/or epidermal growth factor receptor-tyrosine kinase inhibitor(EGFR-TKI)treatment were enrolled in this study.The patients were treated anlotinib(8 mg daily d 1–14)and S-1(60 mg/m^2 d 1–14)and the treatment was repeated every 3 weeks.Treatment was continued until disease progression or unacceptable toxicity occurred.The objective response rate(ORR),disease control rate(DCR),progression-free survival(PFS),and adverse events(AEs)were reviewed and evaluated.Results Forty-one patients were enrolled in the study between June 2018 and December 2018.The total ORR and DCR were 26.8%and 80.5%,respectively.The median PFS was 5.2 months[95%confidence interval(CI),3.9 to 6.6 months].In the univariate analysis,there was a significant difference in the median PFS between patients with brain metastases and those without brain metastases(4.8 months vs 5.9 months,respectively;P=0.039).The Eastern Cooperative Oncology Group(ECOG)performance status(P=0.002),lines of therapy(P=0.015),and therapeutic evaluation(P=0.014)were independent factors that influenced PFS.The most common AEs were hypertension,proteinuria,myelosuppression,gastrointestinal reactions,fatigue,and mucositis.Conclusion Anlotinib plus S-1 is an effective and safe regimen for advanced NSCLC as third-or later-line therapy.

<i>In vitro</i>differentiation of human umbilical cord-derived mesenchymal stem cells into CD34⁺cells via CD34 antibody

CD34+cells differentiated from mesenchymal stem cells (MSCs) have a strong biological function in cardiovascular regeneration. However, the molecular mechanisms of and the methods to improve the CD34+ cell differentiation from MSCs, especially from human MSCs (hUC-MSCs) are still unclear. In the current study, the effect of CD34 antibody on the CD34+ cell differentiation from human umbilical cord (UC)-derived MSCs (hUC-MSCs) is determined. The results have demonstrated that the expression of cd34 protein is significantly increased in hUC-MSCs treated with CD34 antibody. In addition, the cell proliferation is increased in hUC-MSCs after treatment with CD34 antibody. Moreover, the expression of PI3K, AKT, p-AKT proteins, which are signaling molecules related to stem cell differentiation, is increased by CD34 antibody. The results suggest that CD34 antibody could promote the differentiation of hUC-MSCs into CD34+ cells and PI3K/AKT may be involved in this important process.

面向未成年人的AI安全风险:风险澄思、根源透析与治理进路

AI技术给社会带来深刻影响,其创新发展对未成年群体的影响引起社会各界的特别关注。AI在给未成年人提供全新成长空间的同时也带来了安全威胁。鉴于此,文章基于未成年人安全视角,省思AI给未成年人带来的安全风险,并从未成年人的脆弱性、AI系统的内生特性和AI治理策略的适切性三个维度进行根源透析。以信息生态系统理论为依据,从顶层设计、风险防范和个体防护三个层面构建面向未成年人的AI安全风险治理生态系统,构筑面向未成年人的AI安全盾牌,确保给未成年人提供合乎规范设计的AI教育产品,以保障未成年人的安全与权益,进而促进未成年人与AI的协调发展。

Doping Strategy in Nickel-Rich Layered Oxide Cathode for Lithium-Ion Battery

Ni-rich layered oxides have been regarded as the most promising cathode material for next-generation high energy density Li-ion batteries because of their advantages in capacity and cost.However,these cathodes suffer from irreversible structural degradation,fast capacity attenuation as well as seriously reduced safety in their practical applications.Doping strategies with different elements have been employed to address the above issues.In this review,we summarize the research advances of the elemental doping in a Ni-rich layered oxide cathode.The experimental methods and dopant selection rules are briefly introduced.Then we discuss here the effects of the elemental doping from the aspects of the crystal lattice,electronic structure,nanomorphology,and surface stability.In addition,this review surveys the first-principles calculation and advanced structural characterization techniques,which have played important roles in elucidating the structure-performance correlations.Finally,perspectives regarding the future of doping strategy are given.