A blockchain based privacy-preserving federated learning scheme for Internet of Vehicles

The application of artificial intelligence technology in Internet of Vehicles(lov)has attracted great research interests with the goal of enabling smart transportation and traffic management.Meanwhile,concerns have been raised over the security and privacy of the tons of traffic and vehicle data.In this regard,Federated Learning(FL)with privacy protection features is considered a highly promising solution.However,in the FL process,the server side may take advantage of its dominant role in model aggregation to steal sensitive information of users,while the client side may also upload malicious data to compromise the training of the global model.Most existing privacy-preserving FL schemes in IoV fail to deal with threats from both of these two sides at the same time.In this paper,we propose a Blockchain based Privacy-preserving Federated Learning scheme named BPFL,which uses blockchain as the underlying distributed framework of FL.We improve the Multi-Krum technology and combine it with the homomorphic encryption to achieve ciphertext-level model aggregation and model filtering,which can enable the verifiability of the local models while achieving privacy-preservation.Additionally,we develop a reputation-based incentive mechanism to encourage users in IoV to actively participate in the federated learning and to practice honesty.The security analysis and performance evaluations are conducted to show that the proposed scheme can meet the security requirements and improve the performance of the FL model.

STAT3-Dependent Effects of Polymeric Immunoglobulin Receptor in Regulating Interleukin-17 Signaling and Preventing Autoimmune Hepatitis

One-third of patients with autoimmune hepatitis(AIH)have cirrhosis at the time of diagnosis.The relevance of these variables,although unknown,is believed to be critical in AIH because of suspected interactions between the gut microbiome and genetic factors.Dysbiosis of the gut flora and elevated polymeric immunoglobulin receptor(pIgR)levels have been observed in both patients and mouse models.Moreover,there is a direct relationship between pIgR expression and transaminase levels in patients with AIH.In this study,we aimed to explore how pIgR influences the secretion of regenerating islet-derived 3 beta(Reg3b)and the flora composition in AIH using in vivo experiments involving patients with AIH and a concanavalin A-induced mouse model of AIH.Reg3b expression was reduced in pIgR gene(Pigr)-knockout mice compared to that in wild-type mice,leading to increased microbiota disruption.Conversely,exogenous pIgR supplementation increased Reg3b expression and maintained microbiota homeostasis.RNA sequencing revealed the participation of the interleukin(IL)-17 signaling pathway in the regulation of Reg3b through pIgR.Furthermore,the introduction of external pIgR could not restore the imbalance in gut microbiota in AIH,and the decrease in Reg3b expression was not apparent following the inhibition of signal transducer and activator of transcription 3(STAT3).In this study,pIgR facilitated the upregulation of Reg3b via the STAT3 pathway,which plays a crucial role in preserving the balance of the intestinal microbiota in AIH.Through this research,we discovered new molecular targets that can be used for the diagnosis and treatment of AIH.

BnaC03.BIN2 regulates plant height by affecting the main inflorescence length and first effective branch height in Brassica napus L.

Rapeseed(Brassica napus L.)is one of the main oil crops in the world,and increasing its yield is of great significance for ensuring the safety of edible oil.Presently,improving rapeseed plant architecture is an effective way to increase rapeseed yield with higher planting density.However,the regulatory mechanism of rapeseed plant architecture is poorly understood.In this study,a dwarf rapeseed mutant dwarf08(df08)is obtained by ethyl methane sulfonate(EMS)-mutagenesis.The decrease in plant height of df08 is mainly caused by the reduction in main inflorescence length and first effective branch height and controlled by a single semi-dominant gene.The hybrid plants(F1)show a semi-dwarf phenotype.Through map-based cloning and transgenic assay,we confirm that the nonsynonymous single nucleotide variant(SNV)(C to T)in BnaC03.BIN2,which is homologous with Arabidopsis(Arabidopsis thaliana)BIN2,is responsible for the dwarfism of df08.BnaC03.BIN2 interacts with BnaBZR1/BES1 and involves in brassinosteroids(BRs)signal transduction.Proline to Leucine substitution in 284(P284L)enhances the protein stability of BnaC03.bin2-D,disrupts BRs signal transduction and affects the expression of genes regulating cell division,leading to dwarfism of df08.This study provides a new insight for the mechanism of rapeseed plant height regulation and creates an elite germplasm that can be used for genetic improvement of rapeseed architecture.

强制性环境信息披露监管驱动企业绿色创新的机理——基于中国石化的探索性案例研究

企业在环境信息披露下的绿色创新行为,是理解企业绿色转型的重要逻辑,也是探究经济与环境共赢发展的关键视角。基于对中国石化不同阶段环境信息披露监管约束下绿色创新表现的探索式案例分析,本文系统研究了环境信息披露监管激励企业进行绿色创新的内在机制和底层逻辑。研究发现:(1)在中石化未受环境信息披露监管政策约束时,其选择性披露环境信息,绿色专利申请量呈缓慢上升趋势,但在政策潜在约束及正式约束阶段,企业绿色创新受到激励,绿色专利申请量显著增加;(2)基于声誉机制,环境信息披露监管可通过缓解融资约束、促进管理优化、增强销售激励以及吸引外部合作这四个路径推动中国石化绿色创新。本文不仅拓展了对企业的绿色创新效应激励机制研究,也为政府进一步扩大监管主体范围并最终在全国施行环境信息披露监管提供微观经验证据。

价值引领融入“无机化学与化学分析”的课程思政建设

将课程思政应用到“无机化学和化学分析”教学中,更好发挥其价值引领作用。开展课程思政建设,应做到守正与创新。本文以价值引领为切入点,介绍如何将思想政治教育有机融入课程内容设置和课堂讲授等环节,力求培养学生的家国情怀、国际视野、法治意识、生态意识、工程伦理、人文关怀等科学素养,深入践行立德树人,提高本科教学质量。

Qualitative and quantitative analysis of characteristic free and bound phenolics in three colored quinoas

Quinoa is a good source of phenolics,which both exist as free and bound forms.In order to mark clear the characteristic free and bound phenolics in different quinoa samples,in this study,characteristic free and bound phenolics in three colored quinoas including WQ(white quinoa),RQ(red quinoa)and BQ(black quinoa)were investigated.Result showed a total of 14 phenolics both acted as free and bound form were analyzed in three colored quinoas(WQ,RQ and BQ).Gallic acid,vanillic acid,epicatechin,p-coumaric acid and quercetin existed both as free and bound forms were common phenolics in quinoas.The highest total free phenolics(238.10 mg/kg)and bound phenolics(3377.75 mg/kg)were presented in WQ and RQ,respectively.It indicated WQ and RQ were respectively good source of free and bound phenolics.Moreover,characteristic free and bound phenolics in three colored quinoas could be well analyzed by principal component analysis(PCA),indicating it was an effective and reliable method in distinguishing three colored quinoas based on their characteristic free and bound phenolics,respectively.

The Discourse-Historical Approach of Identity Construction in Corporate Promotional Videos for External Publicity Image

Corporate identity construction of external publicity image is an important part of the development of enterprises.Based on Wodak’s discourse-historical approach,this study takes the text of COFCO’s English promotional video as the research object,analyzes the corporate brand image,media image,organizational image,and environmental image constructed by the enterprises from three steps:linguistic expression,discourse strategy,and theme to provide references for Chinese enterprises to enhance their international influence.

基于行为识别的课堂深度学习成绩预测模型研究

课堂学习行为智能识别和大数据分析为课堂高阶认知评价带来契机。利用数据技术挖掘学生课堂学习行为对深度学习成绩的影响关系,解决识别与评价课堂高阶认知不足的现实问题。以英语和化学两门学科为例,以课堂学习行为为自变量,以测试试卷深度学习成绩为因变量,通过高斯消元、回代总样本求均方差最优解等算法,分析出课堂“听讲”“阅读”等8种课堂行为对深度学习成绩的权重影响,构建课堂学习行为与深度学习成绩间的预测模型,依据模型可识别和评价学生的高阶认知是否发生,为常态课堂高阶认知规模化评价提供科学依据和技术支撑。

河南油田耐高温稠油乳化降黏剂优选及乳化机理研究

针对河南油田稠油黏度高、流动性差的问题,对一系列不同类型、不同质量分数的乳化降黏剂配方进行优选,进而研究了高温条件下乳化降黏剂的性能,并探究了最佳降黏剂配方的乳化机理。结果表明,优选出的最佳乳化降黏剂配方为0.4%(w/%)的BY-2,在油水比为7∶3,油藏温度50℃条件下,可产生优异的乳化降黏效果,稠油降黏率高达97.36%。此外,高温对乳化降黏剂的影响较小,在300℃下老化6 h仍能保持优异的油/水界面活性和乳化效果。乳化降黏剂中的碱性组分可与稠油中的石油酸原位生成表面活性物质,进而产生协同增效作用,显著降低油/水界面张力,提升乳化降黏效果。本研究为稠油油田耐高温乳化降黏剂的研制提供了技术支撑。

Interface Migration between Martensite and Austenite during Quenching and Partitioning (Q&P) Process

An Fe-0.2C-1.5Si-1.67Mn steel was subjected to quenching and partitioning （Q＆P） process, and the interface migration between martensite and austenite at an elevated partitioning temperature was observed. The interface migration is excluded in constrained paraequilibrium （CPE） model. Based on ＂endpoint＂ predicted by CPE model the thermodynamic condition of interface migration is analyzed, that is, the difference in the chemical potential of iron in both ferrite （martenisite） and austenite produces the driving force of the iron atoms to migrate from one phase to the other phase. In addition, the interface migration can change the austenite fraction; as a result, the austenite fraction at partitioning temperature may be higher than that at quenching temperature through the interface migration, but this phenomenon cannot be explained by CPE model.

A comparative study between Embosphere~ and conventional transcatheter arterial chemoembolization for treatment of unresectable liver metastasis from GIST

Objective：Transcatheter arterial chemoembolization （TACE） is a standard treatment for hepatocellular carcinoma （HCC） and/or some unresectable liver metastasis tumors.Hypervascular liver metastatic lesions such as metastasis from gastrointestinal stromal tumor （GIST） are an indication for transcatheter arterial embolization （TAE）.The purpose of this study was to evaluate the efficacy and safety of Embosphere（㊣）-TAE （Embo-TAE） in comparison with conventional TACE （cTACE） for the treatment of liver metastasis from GIST.Methods：A total of 45 patients who underwent TACE between Aug 2008 and Feb 2013 were enrolled.Patients with GIST who underwent TAE with Embosphere（㊣） （n=19） were compared with controls who received cTACE （n=26）.The primary end points were treatment response and treatment-related adverse events.The secondary end points were progression-free survival （PFS） and overall survival （OS）.Results：The treatment response of Embo-TAE group was significandy higher than that of the cTACE group （P＜0.001）.The PFS was significandy better in the Embosphere（㊣）-group than in the cTACE group （56.6 and 42.1 weeks,respectively; P=0.003）.However,there was no statistically significant difference in liver toxicity between the two groups （P＞0.05）.The median OS in the Embo-TAE group was longer than that in the cTACE group （74.0 weeks,95％ CI：68.2-79.8 vs.61.7 weeks,95％ CI：56.2-67.2 weeks） （unadjusted P=0.045）.The use of Embo-TAE significantly reduced the risk of death in patients with GIST with liver metastases according to the Cox proportonal hazards regression model [hazard ratio （HR）：0.149; 95％ CI：0.064-0.475].Conclusions：TAE with Embosphcre（㊣） showed better treatment response and delayed tumor progression compared with cTACE.There was no significant difference in treatment-related hepatic toxicities.EmboTAE thus appears to be a feasible and promising approach in the treatment of liver metastasis from GIST.

Prognostic factors for transarterial chemoembolization combined with sustained oxaliplatin-based hepatic arterial infusion chemotherapy of colorectal cancer liver metastasis

Objective： To investigate the prognostic factors in chemorefractory colorectal cancer liver metastasis（CRCLM）patients treated by transarterial chemoembolization（TACE） and sustained hepatic arterial infusion chemotherapy（HAIC）.Methods： Between 2006 and 2015, 162 patients who underwent 763 TACE and HAIC in total were enrolled in this retrospective study, including 110 males and 52 females, with a median age of 60（range, 26–83） years.Prognostic factors were assessed with Log-rank test, Cox univariate and multivariate analyses.Results： The median survival time（MST） and median progression-free survival（PFS） of the 162 patients from first TACE/HAIC were 15.6 months and 5.5 months respectively. Normal serum carbohydrate antigen 19-9（CA19-9, 〈37 U/m L）（P〈0.001） and carbohydrate antigen 72-4（CA72-4, 〈6.7 U/m L）（P=0.026）, combination with other local treatment（liver radiotherapy or liver radiofrequency ablation）（P=0.034） and response to TACE/HAIC（P〈0.001） were significant factors related to survival after TACE/HAIC in univariate analysis. A multivariate analysis revealed that normal serum CA19-9（P〈0.001）, response to TACE/HAIC（P〈0.001） and combination with other local treatment（P=0.001） were independent factors among them.Conclusions： Our findings indicate that serum CA19-9 〈37 U/m L and response to TACE/HAIC are significant prognostic indicators for this combined treatment, and treated with other local treatment could reach a considerable survival benefit for CRCLM. This could be useful for making decisions regarding the treatment of CRCLM.

Chemoselective hydrogenolysis of tetrahydrofurfuryl alcohol to 1,5-pentanediol over Ir-MoO_x/SiO_2 catalyst

In this work, MoOx promoted Ir/SiO2 catalysts were prepared and used for the selective hydrogenolysis of tetrahydrofurfuryl alcohol （THFA） to 1,5-pentanediol in a continuous flow reactor. The effects of different noble metals （Ir, Pt, Pd, Ru, Rh）, supports and Ir contents were screened. Among the investigated catalysts, 4 wt%Ir-MoOx/SiO2 with a Mo/Ir atomic ratio of 0.13 exhibited the best catalytic performance. The synergy between Ix particles and the partially reduced isolated MoOx species attached on them is essential for the excellent catalytic performance of Ix-MoOx/SiO2. The catalyst exhibited a better hydrogenolysis efficiency of THFA with the selectivity of 1,5-pentanediol of 65%-74% at a conversion of THFA of 70%-75% when the initial THFA concentration is ranging from 20 wt% and 40 wt%. And higher system pressure was also in favor of the conversion of THFA. During a stability test, the conversion of THFA and 1,5-pentanediol yield over Ix-MoOz/SiO2 decreased with reaction time, which can be explained by the leaching of Mo species during the reaction.

Carbon-based flexible self-supporting cathode for lithium-sulfur batteries:Progress and perspective

The flexible self-supporting electrode can maintain good mechanical and electrical properties while retaining high specific capacity,which meets the requirements of flexible batteries.Lithium-sulfur batteries(LSBs),as a new generation of energy storage system,hold much higher theoretical energy density than traditional batteries,and they have attracted extensive attention from both the academic and industrial communities.Selection of a proper substrate material is important for the flexible self-supporting electrode.Carbon materials,with the advantages of light weight,high conductivity,strong structural plasticity,and low cost,provide the electrode with a large loading space for the active material and a conductive network.This makes the carbon materials meet the mechanical and electrochemical requirements of flexible electrodes.In this paper,the commonly used fabrication methods and recent research progresses of the flexible self-supporting cathode with a carbon material as the substrate are introduced.Various sulfur loading methods are summarized,which provides useful information for the structural design of the cathode.As the first review article of the carbon-based flexible self-supporting LSB cathodes,it provides valuable guidance for the researchers working in the field of LSB.

Development of an In-Situ Laser Machining System Using a Three-Dimensional Galvanometer Scanner

In this study, a three-dimensional (3D) in-situ laser machining system integrating laser measurement and machining was built using a 3D galvanometer scanner equipped with a side-axis industrial camera. A line structured light measurement model based on a galvanometer scanner was proposed to obtain the 3D information of the workpiece. A height calibration method was proposed to further ensure measurement accuracy, so as to achieve accurate laser focusing. In-situ machining software was developed to realize time-saving and labor-saving 3D laser processing. The feasibility and practicability of this in-situ laser machining system were verified using specific cases. In comparison with the conventional line structured light measurement method, the proposed methods do not require light plane calibration, and do not need additional motion axes for 3D reconstruction;thus they provide technical and cost advantages. The insitu laser machining system realizes a simple operation process by integrating measurement and machining,which greatly reduces labor and time costs.

Biochemical mechanisms of the RNA-induced silencing complex

In less than 10 years since its inception, RNA interference （RNAi） has had extraordinary impact on biomedical science. RNAi has been demonstrated to influence numerous biological and disease pathways. Development and adoption of RNAi technologies have been prolific ranging from basic loss-of-function tools, genome-wide screening libraries to pharmaceutical target validation and therapeutic development. However, understanding of the molecular mechanisms of RNAi is far from complete. The purpose of this brief review is to highlight key achievements in elucidating the bio- chemical mechanisms of the RNA-induced silencing complex and to outline major challenges for the field.

Safety and efficacy of hepatic arterial infusion chemotherapy with raltitrexed and oxaliplatin post-transarterial chemoembolization for unresectable hepatocellular carcinoma

Objective:To investigate the safety,efficacy,and prognostic factors of hepatic arterial infusion chemotherapy(HAIC)with raltitrexed and oxaliplatin post-transarterial chemoembolization(TACE)for unresectable hepatocellular carcinoma(uHCC).Methods:Thirty-seven patients with uHCC who received HAIC with raltitrexed and oxaliplatin post-TACE between June 2014 and December 2016 at our hospital were recruited.The primary endpoint was overall survival(OS),and secondary endpoint was progression-free survival(PFS).The overall response rate(ORR)was evaluated using the modified Response Evaluation Criteria in Solid Tumors.Toxicity was assessed according to the Common Terminology Criteria for Adverse Events(v4.0).The OS and prognostic factors were analyzed using the Kaplan-Meier method,log-rank test,and Cox regression models.Results:Three(8.1%)patients achieved complete response,17(46.0%)patients achieved partial response,and the ORR was54.0%.The median OS and median PFS were 19.0 months and 12.0 months,respectively.The common toxicities included grade 3-4 increased aspartate aminotransferase levels(8/37,21.6%),grade 1-2 hyperbilirubinemia(75.7%,28/37),nonspecific abdominal pain and fever,and grade 2-3 thrombocytopenia(18.9%,7/37);no patients developed grade 3-4 neutropenia.Univariate analysis showed that the tumor diameter(≤50 mm,p=0.028),Barcelona Clinic Liver Cancer(BCLC)stage(p=0.012),hepatitis B virus DNA level(p=0.033),and derived neutrophil-to-lymphocyte ratio(dNLR;derived neutrophils/leukocytes minus neutrophils)(p=0.003)were predictive factors for prognosis.Multivariate analysis showed that patients with BCLC stage B disease(p=0.029)and dNLR<2 before therapy(p=0.004)had better prognosis.Conclusions:HAIC with raltitrexed and oxaliplatin post-TACE is a safe and efficacious therapy for patients with uHCC;in particular,those with BCLC stage B and dNLR<2 have better prognosis.

Construction of a recombinant lentivirus containing human microRNA-7-3 and its inhibitory effects on glioma proliferation

In the present study, we constructed a lentivirus, FIV-CMV-GFP-miR-7-3, containing the microRNA-7-3 gene and the green fluorescent protein gene, and used it to transfect human glioma U251 cells. Fluorescence microscopy showed that 80% of U251 cells expressed green fluorescence. Real-time reverse transcription PCR showed that microRNA-7-3 RNA expression in U251 cells was significantly increased. Proliferation was slowed in transfected U251 cells, and most cells were in the G1 phase of the cell cycle. In addition, the expression of the serine/threonine protein kinase 2 was decreased. Results suggested that transfection with a lentivirus carrying microRNA-7-3 can effectively suppress epidermal growth factor receptor pathway activity in U251 cells, arrest cell cycle transition from GI phase to S phase and inhibit glioma cell growth.

Versatile application of wet-oxidation for ambient CO abatement over Fe(OH)_x supported subnanometer platinum group metal catalysts

The efficient and stable abatement of CO pollutant under ambient conditions is of great significance;however,it remains a formidable challenge.Herein,we report the versatile application of wet oxidation over Fe(OH)x supported subnanometer Pt group metal(PGM)catalysts for the complete removal of CO under ambient temperature and humidity conditions.Typically,the 1.8 wt%Rh/Fe(OH)x catalyst exhibited better durability during a^1400 min run for wet oxidation than for dry CO oxidation.Multiple characterization results including HR-TEM,H2-TPR,and in-situ DRIFTS suggested that Fe(OH)x,with good reducibility,promoted by the subnanometer Rh clusters,provided sites for the adsorption and reaction of O2 and H2 O to form OH species.Subsequently,these OH species reacted with the adsorbed CO on Rh sites with a considerably lower activation energy(9 kJ mol^-1)than that of dissociated 0 species(22 kJ mol^-1),thus rationalizing the outstanding performance of Rh/Fe(OH)x for wet oxidation.Extended experiments with other PGMs revealed a good generality for the application of wet oxidation in the efficient abatement of CO under humid conditions with Fe(OH)x as the support.

Achieving Fine-Grained and Flexible Access Control on Blockchain-Based Data Sharing for the Internet of Things

The traditional centralized data sharing systems have potential risks such as single point of failures and excessive working load on the central node.As a distributed and collaborative alternative,approaches based upon blockchain have been explored recently for Internet of Things(IoTs).However,the access from a legitimate user may be denied without the pre-defined policy and data update on the blockchain could be costly to the owners.In this paper,we first address these issues by incorporating the Accountable Subgroup Multi-Signature(ASM)algorithm into the Attribute-based Access Control(ABAC)method with Policy Smart Contract,to provide a finegrained and flexible solution.Next,we propose a policy-based Chameleon Hash algorithm that allows the data to be updated in a reliable and convenient way by the authorized users.Finally,we evaluate our work by comparing its performance with the benchmarks.The results demonstrate significant improvement on the effectiveness and efficiency.