Preparation and Evaluation of a Self-Nanoemulsifying Drug Delivery System Loaded with Heparin Phospholipid Complex

A self-nanoemulsifying drug delivery system (SNEDDS) was developed to enhance the absorption of heparin after oral administration, in which heparin was compounded with phospholipids to achieve better fat solubility in the form of heparin-phospholipid (HEP-Pc) complex. HEP-Pc complex was prepared using the solvent evaporation method, which increased the solubility of heparin in n-octanol. The successful preparation of HEP-Pc complex was confirmed by differential scanning calorimetry (DSC), Fourier-transform infrared (FT-IR) spectroscopy, NMR, and SEM. A heparin lipid microemulsion (HEP-LM) was prepared by high-pressure homogenization and characterized. HEP-LM can enhance the absorption of heparin after oral administration, significantly prolong activated partial thromboplastin time (APTT) and thrombin time (TT) in mice, and reduce fibrinogen (FIB) content. All these outcomes indicate that HEP-LM has great potential as an oral heparin formulation.     

Fixed-time Consensus Tracking for Second-order Leader-follower Multi-agent Systems with Nonlinear Dynamics Under Directed Topology

In this paper, we address the fixed-time consensus tracking problem of second-order leader-follower multi-agent systems with nonlinear dynamics under directed topology. The consensus tracking algorithm consists of distributed observer and observer-based decentralized controller. The fixed-time distributed observer guarantees that each follower estimates the leader’s state under directed topology within a fixed time, where the upper bound of convergence time is independent on the initial conditions. The fixed-time decentralized controller makes each follower converge to the leader’s state in fixed time via tracking the distributed observer’s state and overcome the nonlinear dynamics without adding linear control terms. Finally, the numerical example is provided to illustrate the effectiveness of the results.

     

Probing into Reverse Bias Dark Current in Perovskite Photodiodes: Critical Role of Surface Defects

Minimizing reverse bias dark current density (J_dark) while retaining high external quantum efficiency is crucial for promising applications of perovskite photodiodes, and it remains challenging to elucidate the ultimate origin of J_dark. It is demonstrated in this study that the surface defects induced by iodine vacancies are the main cause of J_dark in perovskite photodiodes. In a targeted way, the surface defects are thoroughly passivated through a simple treatment with butylamine hydroiodide to form ultrathin 2D perovskite on its 3D bulk. In the passivated perovskite photodiodes, J_dark as low as 3.78 × 10^-10 A cm^-2 at -0.1 V is achieved, and the photoresponse is also enhanced, especially at low light intensities. A combination of the two improvements realizes high specific detectivity up to 1.46 × 10¹² Jones in the devices. It is clarified that the trap states induced by the surface defects can not only raise the generation-recombination current density associated with the Shockley–Read–Hall mechanisms in the dark (increasing J_dark), but also provide additional carrier recombination paths under light illumination (decreasing photocurrent). The critical role of surface defects on J_dark of perovskite photodiodes suggests that making trap-free perovskite thin films, for example, by fine preparation and/or surface engineering, is a top priority for high-performance perovskite photodiodes.     

多智能体沿多条给定路径编队运动的有向协同控制

研究了在有向通信连接下二阶积分器描述的多智能体沿多条给定路径编队运动的控制器设计及其稳定性分析问题. 智能体的动态和指定路径都是在固定直角坐标系下描述的. 通过引入路径函数来设计路径跟踪控制, 根据路径函数与弧长的关系来设计编队控制律, 使得多智能体沿期望路径的位置和速度在规定队形下达到一致. 利用图论证明, 当通信拓扑对应的有向图具有全局可达点时, 设计的编队控制系统是渐近稳定的. 本文设计的有向协同控制律可以应用于区域的信息优化采集.     

基于线特征和控制点的可见光和SAR图像配准

以具有典型人造目标的可见光和SAR (Synthetic aperture radar)图像为研究对象,提出一种自适应多尺度快速Beamlet变换方法提取人造目标在可见光和SAR图像的共有特征---线特征, 并基于线特征构造控制点,设计了一种基于控制点特征的匹配度函数,采用基于特征一致的粗配准和基于控制点的精确配准方法,对待配准图像实现由粗到精的自动配准. 实验表明,在可见光和SAR图像存在较大灰度差异、旋转和平移的情况下,该算法仍然能够精确配准图像.     

ACOA-RBF网络模型在短期负荷预测中的应用

为了进一步提高RBF神经网络的性能,实现准确、快速预测短期电力负荷的目的,将蚁群优化算法（ACOA）作为RBF神经网络的学习算法,建立了一种新的蚁群优化算法的RBF（ACOA-RBF）网络预测模型,利用山西某地区电网的历史数据进行短期负荷预测。仿真表明,这一算法与传统的RBF神经网络预测方法相比,能达到更好的预测效果。该优化算法改善了径向基神经网络的泛化能力,提高了山西电网短期负荷预测的精度,可有效用于电力系统的短期负荷预测。     

不同菌材栽培糙皮侧耳营养品质综合评价

摘 要：目的 分析不同菌材栽培糙皮侧耳(Pleurotus ostreatus)生长及营养品质差异,并对其营养品质进行综合评价。方法 以贵州5种常见菌材锥栗(Castanea henryi)、构树(Broussonetia papyrifera)、刺槐(Robinia pseudoacacia)、光皮桦(Betula luminifera)、青冈(Quercus glauca)为主要培养料栽培糙皮侧耳,对糙皮侧耳菌丝生长、子实体主要农艺性状及营养品质进行分析。结果 糙皮侧耳在光皮桦培养基上菌丝生长速率更快,在锥栗和刺槐栽培基质中子实体主要农艺性状更好。刺槐栽培基质中糙皮侧耳子实体粗蛋白、Cu、Zn、K元素含量最高,锥栗栽培基质中糙皮侧耳子实体多糖、Na、Mg、Fe、Ca元素含量最高。以5种菌材栽培的糙皮侧耳子实体总氨基酸、必需氨基酸及总药用氨基酸均为刺槐>青冈>光皮桦>构树>锥栗。5种菌材栽培的糙皮侧耳子实体呈味氨基酸主要为甜味和苦味氨基酸,其中以光皮桦栽培的糙皮侧耳子实体鲜味和甜味氨基酸含量最高。必需氨基酸营养品质评价及营养品质综合评价结果表明刺槐栽培糙皮侧耳子实体综合营养品质更好。Fe、苏氨酸、丙氨酸、谷氨酸、精氨酸、天冬氨酸、组氨酸、Zn和多糖是5种菌材栽培的糙皮侧耳子实体主要差异营养成分。相关性分析结果显示菌材营养成分主要与糙皮侧耳菌丝生长、子实体主要农艺性状和矿物质元素含量显著相关。结论 不同营养成分的菌材对糙皮侧耳子实体生长和营养品质的影响不同,刺槐更适合作为生产糙皮侧耳主栽菌材。     

基于非靶向代谢组技术研究不同发酵温度酱油中代谢产物差异

目的 基于非靶向代谢组学研究不同发酵温度(25、30、35、40℃)酱油中代谢产物差异。方法 采用超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)检测不同发酵温度的酱油样品的代谢物,通过主成分分析(principal component analysis,PCA)、正交偏最小二乘判别分析法(orthogonal partial least square-discriminant analysis,OPLS-DA)等统计学分析,筛选不同温度发酵酱油的差异代谢物。结果 4种不同发酵温度酱油样品共鉴定出14类266个代谢物。其中,25℃下发酵酱油中氨基酸和有机酸类化合物的含量最高,而35℃发酵酱油的中氨基酸、脂肪酸类和生物碱化合物的相对含量最高。通过OPLS-DA分析研究,鉴定出了37种显著差异代谢物质(变量投影重要性>1),包括有氨基酸9种,糖类和有机酸各5种,生物碱和脂肪酸各4种,芳香类化合物3种,香豆素类、胺类和酚类各2种,黄酮类1种。结论 该研究明...     

Synthetic curli enables efficient microbial electrocatalysis with stainless-steel electrode

Microbial electrocatalysis systems (MES) provide a cutting-edge solution to global problems associated with the environment and energy, but practical applications are hindered by the expensive electrode materials. Although stainless steel (SS) has been proposed as a promising inexpensive candidate, poor cell/SS interaction results in a low performance for MES. Here, a new synthetic biology approach was established for reinforcing the cell/SS interaction. Hybridized curli nanofibers fused with a metal-binding domain were heterogeneously expressed onto the cell surface, which realized efficient cell binding with the SS electrode. Consequently, it enabled a ~420-fold improvement of the anodic power output and a substantial enhancement of the cathodic Coulombic efficiency (from 0.6 to 4% to over 80%) with an SS electrode. This work demonstrates low-cost MES with an SS electrode and introduces a new avenue to engineer the cell/electrode interaction, which is promising for future practical applications of MES.     

一种新型最优检索结果的发现与论证

该文基于量化数据证明如下观点:检索结果中,本源正确的检索结果应为最佳(即蕴含的信息符合客观逻辑和自然规律的检索结果).在此基础上,提出了一种新型基于正确性的信息检索评测方法.文中讨论的信息正确性是一种事实性的客观正确性,不随用户主观判断产生正确性的变化,与依赖用户满意度的相关结果具有显著差异.当前,信息检索方向的研究尚未关注检索结果本源正确性的自动检测与应用,且尚未提出相应的排序优化算法.文中即针对这一问题进行量化的科学验证,并给出相关研究的评测框架.