Blockchain-based data transmission control for Tactical Data Link

Tactical Data Link(TDL)is a communication system that utilizes a particular message format and a protocol to transmit data via wireless channels in an instant,automatic,and secure way.So far,TDL has shown its excellence in military applications.Current TDL adopts a distributed architecture to enhance anti-destruction capacity.However,It still faces a problem of data inconsistency and thus cannot well support cooperation across multiple militarily domains.To tackle this problem,we propose to leverage blockchain to build an automatic and adaptive data transmission control scheme for TDL.It achieves automatic data transmission and realizes information consistency among different TDL entities.Besides,applying smart contracts based on blockchain further enables adjusting data transmission policies automatically.Security analysis and experimental results based on simulations illustrate the effectiveness and efficiency of our proposed scheme.

Robust Output Feedback Control for Fractional Order Nonlinear Systems with Time-varying Delays

Robust controller design problem is investigated for a class of fractional order nonlinear systems with time varying delays. Firstly, a reduced-order observer is designed. Then, an output feedback controller is designed. Both the designed observer and controller are independent of time delays. By choosing appropriate Lyapunov functions, we prove the designed controller can render the fractional order system asymptotically stable. A simulation example is given to verify the effectiveness of the proposed approach. © 2014 Chinese Association of Automation.

End-group modulation of phenazine based non-fullerene acceptors for efficient organic solar cells with high open-circuit voltage

Phenazine-based non-fullerene acceptors(NFAs)have demonstrated great potential in improving the power conversion efficiency(PCE)of organic solar cells(OSCs).Halogenation is known to be an effective strategy for increasing optical absorption,refining energy levels,and improving molecular packing in organic semiconductors.Herein,a series of NFAs(Pz IC-4H,Pz IC-4F,Pz IC-4Cl,Pz IC-2Br)with phenazine as the central core and with/without halogen-substituted(dicyanomethylidene)-indan-1-one(IC)as the electron-accepting end group were synthesized,and the effect of end group matched phenazine central unit on the photovoltaic performance was systematically studied.Synergetic photophysical and morphological analyses revealed that the PM6:Pz IC-4F blend involves efficient exciton dissociation,higher charge collection and transfer rates,better crystallinity,and optimal phase separation.Therefore,OSCs based on PM6:Pz IC-4F as the active layer exhibited a PCE of 16.48%with an open circuit voltage(Voc)and energy loss of 0.880 V and 0.53 e V,respectively.Accordingly,this work demonstrated a promising approach by designing phenazine-based NFAs for achieving high-performance OSCs.

Molecular packing tuning via chlorinated end group enables efficient binary organic solar cells over 18.5%

Designing novel nonfullerene acceptors(NFAs)is of vital importance for the development of organic solar cells(OSC).Modification on the side chain and end group are two powerful tools to construct efficient NFAs.Here,based on the high-performance L8BO,we selected 3-ethylheptyl to substitute the inner chain of 2-ethylhexyl,obtaining the backbone of BON3.Then we introduced different halogen atoms of fluorine and chlorine on 2-(3-oxo-2,3-dihydro-1Hinden-1-ylidene)malononitrile end group(EG)to construct efficient NFAs named BON3-F and BON3-Cl,respectively.Polymer donor D18 was chosen to combine with two novel NFAs to construct OSC devices.Impressively,D18:BON3-Cl-based device shows a remarkable power conversion efficiency(PCE)of 18.57%,with a high open-circuit voltage(V_(OC))of 0.907 V and an excellent fill factor(FF)of 80.44%,which is one of the highest binary PCE of devices based on D18 as the donor.However,BON3-F-based device shows a relatively lower PCE of 17.79%with a decreased FF of 79.05%.The better photovoltaic performance is mainly attributed to the red-shifted absorption,higher electron and hole mobilities,reduced charge recombination,and enhanced molecular packing in the D18:BON3-Cl films.Also,we performed stability tests on two binary systems;the D18:BON3-Cl and D18:BON3-F devices maintain 88.1%and 85.5%of their initial efficiencies after 169 h of storage at 85°C in an N2-filled glove box,respectively.Our work demonstrates the importance of selecting halogen atoms on EG and provides an efficient binary system of D18:BON3-Cl for further improvement of PCE.

Privacy preservation in permissionless blockchain:A survey

Permissionless blockchain,as a kind of distributed ledger,has gained considerable attention because of its openness,transparency,decentralization,and immutability.Currently,permissionless blockchain has shown a good application prospect in many fields,from the initial cryptocurrency to the Internet of Things(IoT)and Vehicular Ad-Hoc Networking(VANET),which is considered as the beginning of rewriting our digital infrastructure.However,blockchain confronts some privacy risks that hinder its practical applications.Though numerous surveys reviewed the privacy preservation in blockchain,they failed to reveal the latest advances,nor have they been able to conduct a unified standard comprehensive classification of the privacy protection of permissionless blockchain.Therefore,in this paper,we analyze the specific characteristics of permissionless blockchain,summarize the potential privacy threats,and investigate the unique privacy requirements of blockchain.Existing privacy preservation technologies are carefully surveyed and evaluated based on our proposed evaluation criteria.We finally figure out open research issues as well as future research directions from the perspective of privacy issues.

Kunming mouse strain is less susceptible to elastase-induced abdominal aortic aneurysms

Background:Porcine pancreatic elastase(PPE)is successfully used to induce abdominal aortic aneurysm(AAA)in mice.However,differences between mouse strains in susceptibility to PPE induction have been reported.Kunming mouse is one of the most frequently used strains in China but whether it is suitable for induction of AAA by PPE application remains unclear.Methods:PPE infusion(1.5 units/ml)in temporary controlled aorta was performed to induce AAAs in both C57BL/6J and Kunming mice.Phosphatebuffered saline(PBS)application was used as vehicle control.The aorta diameters of all mice were measured at days 0 and 14 after surgery to evaluate the AAA formation.Results:After 14 days of PPE or PBS infusion,all mice were sacrificed and aorta tissues were collected for histological staining analysis.At the 14th day after infusion,PPE successfully induced aortic dilation in Kunming mice and typical AAA in C57BL/6J mice.The aorta diameter increased by 0.23 mm in Kunming mice after PPE infusion,while it was 0.72 mm in the C57BL/6J strain.PPE induced mild elastin degradation,smooth muscle cell(SMC)depletion and mural leucocyte infiltration in Kunming mice,but in PPE-sensitive C57BL/6J mice,it induced total loss of SMCs,elastin disappearance and diffused infiltrated leucocytes in aortic aneurysmal segments.The effects of PPE in inducing angiogenesis and upregulating matrix metalloproteinase 2 and 9 expression in Kunming mice were also weaker than that in C57BL/6J mice.Conclusion:At the reported dose of PPE,Kunming mouse is not as susceptible to AAA formation as C57BL/6J mice.The failure of PPE to induce AAA formation in Kunming mice may be associated to its inability to boost a strong inflammatory response.

组氨酸激酶和组氨酸磷酸酶在肿瘤中的作用

蛋白磷酸化修饰是最常见、最重要的蛋白质翻译后修饰方式。磷酸化修饰在细胞的增殖、分化、发育和代谢等生物学过程中发挥了重要的调控功能,与肿瘤的发生和发展也密切相关。蛋白激酶和磷酸酶对蛋白磷酸化修饰具有普遍的开/关调控作用。真核生物的蛋白磷酸化主要发生在丝氨酸、苏氨酸和酪氨酸残基,他们在肿瘤发生和发展中的作用已经得到了广泛的研究。但关于组氨酸磷酸化的研究受限于质谱分析和富集技术的发展研究较少。近年来,随着相关技术的快速发展和新的组氨酸磷酸酶的发现,使得研究人员越来越多关注到组氨酸磷酸化在肿瘤中的作用。因此,本文旨在对组氨酸磷酸化调控相关的组氨酸激酶和组氨酸磷酸酶在肿瘤中的作用作一综述。

Line-scanning microscopy with laterally symmetric imaging using simultaneous cross-line illumination

Using an on-the-fly scanning scheme, line confocal microscopy can obtain complex structures of large biological tissues with high throughput. Yet, it suffers from lateral imaging asymmetry and thus introduces the potential deformations of the observation results. Here, we propose cross-line illumination microscopy (cLIM) that acquires the imaging data of two perpendicular directions simultaneously through the same objective lens in a line scanning and utilizes two-direction deconvolution fusion to achieve lateral symmetric imaging performance.Imaging fluorescence beads indicates that cLIM reduces lateral resolution asymmetry from 46.1%to 2.5%and improves lateral resolution by 31.0%, compared with traditional line-scanning imaging. Compared with commercial point-confocal microscopy, the cLIM has a 25.84×increase in imaging speed and 1.93×better background-suppressing ability when imaging an 11,306μm×7783μm×100μm mouse kidney slice. We also show the advantages of the cLIM in observing direction-sensitive texture features by imaging a muscular tissue slice. cLIM offers a novel solution to achieve laterally symmetric line-scanning imaging with simple modifications while maintaining high throughput and accuracy for imaging large-scale samples.

Gender differences in the relationship between plasma lipids and fasting plasma glucose in non-diabetic urban Chinese popula- tion： a cross-section study

The association between dyslipidemia and elevated fasting glucose in type 2 diabetes is well known. In non-diabetes, whether this association still exists, and whether dyslipidemia is an independent risk factor for high fasting plasma glucose （FPG） levels are not clear. This cross-sectional study recruited 3460 non-diabetic Chinese subjects （1027 men, and 2433 women, aged 35-75 years old） who participated in a health survey. Men and women were classified into tertiles by levels of plasma lipids respectively. In women, the prevalence of impaired fasting glucose （IFG） was decreased with increased HDL-C. A stepwise increase in HDL-C was associated with decreasing FPG levels （lowest tertiles, FPG： 5.376 ± 0.018; middle tertiles, 5.324± 0.018; highest tertiles, 5.276±0.018mmol/L; P = 0.001）. Reversely, FPG levels increased from lowest tertiles to highest tertiles of LDL-C, TC, and TG. we found that women in the first tertile with lower HDL-C level had a 1.75-fold increase in risk of IFG compared with non-diabetic women in the third tertile with higher HDL-C level （OR： 1.75; 95% CI： 1.20-2.56）. In men, no significant association was found. We took age, BMI, waist/hip ratio, education, smoking, alcohol drinking, and physical exercise as adjusted variables. In Chinese non-diabetic women, dyslipidemia is independently associated with high levels of FPG; TG, HDL-C, and LDL-C are predictors of IFG independent of BMI and waist/hip ratio.

Dynamic parameter identification of upperlimb rehabilitation robot system based on variable parameter particle swarm optimisation

To solve the problem of uncertain parameters in dynamic modelling of upper-limb rehabilitation robots,a dynamic parameter identification method based on variable parameters particle swarm optimisation(PSO)is developed.Based on the dynamic model of the system,the algorithm changes the inertia parameter and learning law of the basic PSO algorithm from the fixed-parameter to the function that changes with the number of iterations.It solves the problems of small search space in the early stage and slow convergence speed in the later stage of the basic PSO algorithm,which greatly improves its identification accuracy.Finally,through the comparison and analysis of the simulation results,compared with those of the least square(LS)and unmodified PSO identification algorithms,a great improvement in the identification accuracy of the algorithm is achieved.The control effect in the actual control system is also much better than those of the LS and PSO algorithms.

分割氢键有机框架的孔道空间提升光催化CO_(2)还原效率

氢键有机框架材料(HOFs)在催化领域具有巨大的潜力,但其孔道空间在去除溶剂后易塌陷,限制了其在光催化能源转换和存储方面的应用.本研究采用孔道分割策略成功设计并合成了一种稳定孔道结构、高效光催化CO_(2)还原活性的HOF催化剂.H4TBAPy分子通过与HOF孔道中大量的CH…π相互作用锚定自身,并将HOF的大孔道分隔成多个小空间,显著增加了HOF框架的稳定性.同时,富电子属性的H4TBAPy分子提升了HOF体系中电子的传输速率,从而提高了催化活性.这项研究为设计稳定、高性能的HOFs光催化剂提供了新策略.

先进复合材料在航空装备发展中的地位与作用

“一代材料,一代装备”阐明了材料技术在装备发展中的重要性。航空装备的发展历程表明,一代新材料的出现支撑了一代新装备的研发,一代新装备的研制牵引一代新材料的应用。不同航空装备应用不同的结构材料,和三代机相比,四代战斗机用结构材料的最大差别是先进复合材料的大量应用。本文介绍了国内先进复合材料技术的发展历程和现状、复合材料技术发展面临的机遇和挑战及今后国内先进复合材料技术的发展重点。

基于透明活性层的高效柔性半透明有机太阳能电池

柔性和半透明是有机太阳能电池(OSCs)的重要优势,受到科学界和工业界的广泛关注.目前,提高柔性半透明OSCs(ST-OSCs)性能的关键是柔性透明电极(FTEs)和吸光活性层.本文制备了透过率为84.8%的复合FTEs,这使得活性层可以高效捕获太阳光,优化了器件中的光管理.此外,在活性层中采用了多种成熟的策略,包括构筑类合金近红外受体(Y6:m-BTP-PhC6)和稀释可见光范围强吸收的给体(PM6),使得每个光子被精确利用,有效平衡了ST-OSCs效率和透过率之间的冲突.利用以上策略,提高了活性层中可见光的透过和近红外光的吸收,最终获得了高透明度的活性层,其平均可见光透过率(AVT)值为39.3%.基于此,柔性不透明和半透明OSCs分别获得了16.44%和11.48%的能量转换效率,这是目前柔性ST-OSCs的最高效率之一.本工作对实现具有优异鲁棒性和高性能的ST-OSCs具有重要的指导意义,也为其实际应用迈出了重要一步.