Multifunctional fibrous wound dressings for refractory wound healing

Refractory wounds have always been an important issue to healthcare systems, whose healing process is always delayed by multiple factors, including bacterial infections, chronic inflammation, and excessive exudates, etc. Employing multifunctional wound dressings is recognized as an effective strategy to deal with refractory wounds, which has yielded promising outcomes in recent years. Among these advanced wound dressings, fibrous dressings have gained growing attention due to their unique merits. Such wound dressings have demonstrated great potential in delivering theranostic agents, such as antibacterial agents, anti-inflammatory drugs, growth factors, and diagnostic probes, etc., for the purposes of accelerating wound healing. This paper reviews the development of multifunctional fibrous dressings and their applications in treating refractory wounds. The construction approaches of novel fibrous dressing with capabilities of antibacterial, anti-inflammation, exudate management and diagnosis were also introduced. Furthermore, the existing problems and challenges are also discussed briefly.     

突出矿井瓦斯抽放限制影响因素的AHP-熵权法评价模型

为提高煤与瓦斯突出矿井瓦斯抽放效果,建立了3个一级指标、14个二级指标的突出矿井瓦斯抽放限制影响因素评价指标体系,利用AHP和熵权法分别确定指标因子主、客观权重.通过实地调研分析和反馈验证了AHP-熵权法的可行性和正确性,利用加权平均法确定评价模型的综合权重.研究表明:封孔方式、钻孔半径、抽放时间、煤体裂隙发育程度和抽放负压是目前影响煤矿瓦斯抽放效果的主控因素.     

Dynamical analysis,circuit realization,and application in pseudorandom number generators of a fractional-order laser chaotic system

A new five-dimensional fractional-order laser chaotic system (FOLCS) is constructed by incorporating complex variables and fractional calculus into a Lorentz-Haken-type laser system. Dynamical behavior of the system, circuit realization and application in pseudorandom number generators are studied. Many types of multi-stable states are discovered in the system. Interestingly, there are two types of state transition phenomena in the system, one is the chaotic state degenerates to a periodical state, and the other is the intermittent chaotic oscillation. In addition, the complexity of the system when two parameters change simultaneously is measured by the spectral entropy algorithm. Moreover, a digital circuit is design and the chaotic oscillation behaviors of the system are verified on this circuit. Finally, a pseudo-random sequence generator is designed using the FOLCS, and the statistical characteristics of the generated pseudo-random sequence are tested with the NIST-800-22. This study enriches the research on the dynamics and applications of FOLCS.     

Ultrahigh Loading Copper Single Atom Catalyst for Palladium-free Wacker Oxidation

Wacker oxidation is an industry-adopted process to transform olefins into value-added epoxides and carbonyls. However, traditional Wacker oxidation involves the use of homogeneous palladium and copper catalysts for the olefin addition and reductive elimination. Here, we demonstrated an ultrahigh loading Cu single atom catalyst(14% Cu, mass fraction) for the palladium-free Wacker oxidation of 4-vinylanisole into the corresponding ketone with N-methylhydroxylamine hydrochloride as an additive under mild conditions. Mechanistic studies by ¹⁸O and deuterium isotope labelling revealed a hydrogen shift mechanism in this palladium-free process using N-methylhydroxylamine hydrochloride as the oxygen source. The reaction scope can be further extended to Kucherov oxidation. Our study paves the way to replace noble metal catalysts in the traditional homogeneous processes with single atom catalysts.     

2017—2019 年北京地区实验动物质量抽检结果分析

摘要:目的 比对分析 2017—2019 年北京地区实验动物微生物及遗传质量监测结果,为实验动物产业发展提供参考。 方法 按照国家和地方现行实验动物检测标准,对北京地区实验动物生产单位进行抽检,并发布检测报告。按照报告数据,对此阶段小鼠、大鼠、豚鼠、地鼠、兔、犬、猴和小型猪共 8 个品种的实验动物按照品种、等级、单位等进行分类,分析质量问题,并与 2014—2016 年同期实验动物质量比对,分析变化趋势。 结果 2017—2019 年分别抽检动物 144、131 和 135 批次,检出不合格批次分别为 30、15 和 17 批。 不合格主要因素为兔、犬及猪免疫不达标(20 批) ,病原感染 20 批,未发现遗传变异。 与 2014—2016 年同期相比,未检出遗传问题相同,免疫不达标状况好转,但病原感染出现上升。 结论 通过质量分析比对,能够为实验动物产业健康发展提供数据支持。     

基于多环返工串行生产线的性能优化建模

为评价和优化串行多环返工生产系统的生产性能表现，结合质量管理与精益生产的理念，区别于传统的返工机制，提出一种全新的“即刻返工”检查机制，将生产系统建模扩展至多机多缓冲区的复杂生产系统.基于生产系统的两大要素，机器与缓冲区的生产状态变化，依据概率论与马氏定理，构建缓冲水平的动态概率转移矩阵，以在制品库存水平及系统平均生产率作为研究指标，针对生产设备及缓冲区展开瞬态分析，通过迭代计算，表明设置合理的系统规模与缓冲区阈值能达到优化系统生产性能的目的，并通过数值实验验证其有效性.     

民族高校工商管理专业实践教学体系创新研究

围绕工商管理专业培养具有较强实践能力和高素质管理人才的目标,分析当前实践教学中的误区,通过构建全社会参与的工商管理专业人才实践教学社会网络,建立贯穿大学四年学习全周期的五大实践教学培养体系,对工商管理专业学生进行基础素养实践能力和专业素养实践能力培养,探索工商管理专业人才实践能力培养模式和体系。     

基于LQG控制的整车8-DOF系统振动分析

建立了整车8-DOF系统动力学模型,考虑了主动悬架控制,并增设了主动座椅控制,设计了车辆主动悬架系统的LQG控制器。基于Matlab仿真平台建立了整车8-DOF系统动力学仿真模型,对所得最优控制策略下的动态响应进行了仿真验证。仿真结果表明:为了改善人椅系统质心及车身质心的跳振性能需要在一定程度上弱化各轮轮胎动位移性能。从控制效能上来看,该最优控制器能够满足各行驶状态下对悬架性能的要求,改善了车辆的行驶平顺性。