微流控技术在脂质纳米载体制备中的应用研究进展

脂质纳米载体是递送各种药物的重要工具,尽管在过去数年间得到了发展,但却仍然受到制造工艺的限制。例如,传统方法生产的脂质纳米载体存在粒径不均一、产量低以及批次间差异大等诸多局限性。为了克服这些阻碍,微流控技术在脂质纳米载体制备中的应用逐渐增多,其能够以更高的产量获得粒径均一、性能可控的脂质纳米载体。本文综述了微流控技术在脂质体、脂质纳米颗粒等纳米载体制备中的优势,并且总结了基于微流控技术的脂质纳米载体用于小分子、寡核苷酸药物递送的最新研究进展。

基于不同碳链长度二元酸的脂肪族聚酯的合成及性能

分别以5种不同碳链长度的脂肪族二元酸(C4、C6、C8、C10、C12)和丁二醇为单体,采用先酯化后缩聚的两步法合成一系列脂肪族聚酯:聚丁二酸丁二醇酯(PBS)、聚己二酸丁二醇酯(PBA)、聚辛二酸丁二醇酯(PBSu)、聚癸二酸丁二醇酯(PBSe)和聚十二烷二酸丁二醇酯(PBD)。研究了脂肪族二元酸单体的碳链长度对5种聚酯的结构、热性能和力学性能的影响。研究表明,5种聚酯的Mw在125000~250200之间,其结果与特性黏度具有一致性。随着脂肪族二元酸碳链长度的增加,聚酯的T_c,T_m和T_g均先降低后升高;PBSu(C8)的结晶度最高(71.2%),PBA(C6)的结晶度最低(33.8%)。随着碳链长度的增加,聚酯的初始分解温度逐渐向高温区移动,聚酯的拉伸强度逐渐降低;断裂伸长率先增加后降低,PBS(C4)的拉伸强度最大(58.55 MPa),PBSu(C8)的断裂伸长率最大(897.2%)。5种脂肪族聚酯均属于典型的假塑性流体。

Hydrogen solubility prediction for diesel molecules based on a modified Henry equation

Diesel hydrotreatment removes heteroatoms and polycyclic aromatics in diesel in the presence of highpressure hydrogen gas.The hydrogen solubility is the basis for hydrogen consumption prediction and process design/optimization.In the presented study,we established a method to predict the hydrogen solubility of diesel molecules and mixture.A modified Henry equation was proposed to illustrate the hydrogen solubility variation among the temperature and pressure.The parameters of the modified Henry equation for typical molecules were regressed from literature data.Then we established an empirical correlation between the parameter and the structure and property of molecules.The method was then combined with a molecular-level compositional model to accurately predict the hydrogen solubility in diesel,illustrating the validity of the method.

Liquid Chromatography-electrospray Ionization Tandem Mass Spectrometry for Simultaneous Determination of Metformin and Glimepiride in Beagle Dog Plasma and Bioequivalence Study

A sensitive and selective liquid chromatography-electrospray ionization tandem mass spectrometry（LC- ES1-MS/MS） was used for the simultaneous determination of metformin and glimepiride in beagle dog plasma with glipizide as internal standard（IS）. After simplified protein precipitation with methanol, both the analytes and IS were chromatographed on a Zorbax CN column via gradient elution with methanol（containing 5 mmol/L ammonium ace- tate） and 5 mmol/L aqueous ammonium acetate as the mobile phase. Detection was performed by multiple reaction monitoring（MRM） scanning via ESI source operated in positive ionization mode. Specificity, linearity, accuracy, pre- cision, recovery, matrix effect and stability were validated for metformin and glimepiride in beagle dog plasma. The calibration curves were linear in a concentration range of 10-10000 ng/mL for metformin and 4-4000 ng/mL for glimepiride with both correlation coefficients higher than 0.99. The recoveries obtained for the analytes and IS were all between 82.7% and 101.2%. The method exhibited excellent performance in terms of selectivity, robustness, short analytical time and simplicity of sample preparation. Finally, the proposed method was applied to a bioequivalence study of self-made bilayer tablet and commercial formulation containing 500 mg of metformin and 1 mg of glimepi- ride in beagle dogs.

Production of biscuits by substitution with different ratios of yellow pea flour

To promote the commercialization of yellow pea flour(YPF)due to its nutritional benefits.Four biscuits with different YPF ratio(10%–50%)were conducted to explore the optimal addition percentage.The effects of YPF on the rheological and baking performance of biscuits were performed.The results showed that the substitution ratio of YPF and milling methods had a critical impact on the rheological properties of dough.The dough stability decreased graduallywhile a softening degree increased with YPF ratio increased.In a term of biscuits,the dimensions of length(L),width(W),thickness(T)and color(L*)of biscuits reduced as YPF addition ratio increased,while colors(a*and b*)and hardness apparently increased.In addition,milling methods had a great influence on the texture and sensory evaluation of four biscuits.The dimensions and color parameters of biscuits from fine flours were larger than that from coarse flours,whereas hardness from fine flours was relatively softer,indicating flour with fine particle size could accelerate the extension and expansion of dough network,and improve Maillard reaction during baking.The highest sensory score for short and tough biscuits was obtained given at YPF ratio of 30%without compromising the qualities of biscuits.

Stochastic programming based multi-arm bandit offloading strategy for internet of things

In order to solve the high latency of traditional cloud computing and the processing capacity limitation of Internet of Things(IoT)users,Multi-access Edge Computing(MEC)migrates computing and storage capabilities from the remote data center to the edge of network,providing users with computation services quickly and directly.In this paper,we investigate the impact of the randomness caused by the movement of the IoT user on decision-making for offloading,where the connection between the IoT user and the MEC servers is uncertain.This uncertainty would be the main obstacle to assign the task accurately.Consequently,if the assigned task cannot match well with the real connection time,a migration(connection time is not enough to process)would be caused.In order to address the impact of this uncertainty,we formulate the offloading decision as an optimization problem considering the transmission,computation and migration.With the help of Stochastic Programming(SP),we use the posteriori recourse to compensate for inaccurate predictions.Meanwhile,in heterogeneous networks,considering multiple candidate MEC servers could be selected simultaneously due to overlapping,we also introduce the Multi-Arm Bandit(MAB)theory for MEC selection.The extensive simulations validate the improvement and effectiveness of the proposed SP-based Multi-arm bandit Method(SMM)for offloading in terms of reward,cost,energy consumption and delay.The results showthat SMMcan achieve about 20%improvement compared with the traditional offloading method that does not consider the randomness,and it also outperforms the existing SP/MAB based method for offloading.

计算机建模在口服缓控释片体外释放曲线预测中的应用

缓控释制剂是能降低药物毒副作用、提高患者依从性和增强疗效的理想制剂,其中口服缓控释片的应用最为广泛。制剂体外释放与药物的体内吸收密切相关,然而目前的体外释放实验均为劳动密集型和破坏性的,大数据的缺乏也导致难以建立良好的体内外相关性。计算机建模作为一种可将客观原理转化为数学模型的技术手段,在数据预测方面有很大的前景。本综述探讨了可用于口服缓控释片体外释放曲线预测的计算机建模手段,并进一步讨论了可提高模型准确度的辅助技术,为药物的开发提供了新的思路。

微泡超声造影剂的研究与应用概况

由于超声成像具有非侵入性、相对简便、无电离辐射等特点,已被广泛用于各个领域。超声造影剂在超声成像中发挥着重要作用,通常由软壳或硬壳材料组成,尺寸从纳米到微米不等,功能从最初的成像诊断发展成诊断、治疗一体化模式。部分上市的超声造影剂(例如Levovist■、Optison■、Definity■和Sonovue■)已在欧洲、亚洲等地区用于临床超声检查。该综述重点介绍了微泡超声造影剂的研究进展及其临床应用,以期为新型超声造影剂的开发提供参考。

Composite electrolyte with self-inserted structure and all-trans F conformation provides fast Li^(+) transport for solid-state Li metal batteries

Solid-state Li metal battery has attracted increasing interests for its potentiallyhigh energy density and excellent safety assurance, which is a promising candidatefor next generation battery system. However, the low ionic conductivityand Li^(+) transport number of solid-state polymer electrolytes limit their practicalapplication. Herein, a composite polymer electrolyte with self-insertedstructure is proposed using the layered double hydroxides (LDHs) as dopant toachieve a fast Li^(+) transport channel in poly(vinylidene-co-trifluoroethylene) [P(VDF-TrFE)] based polymer electrolyte. In such a composite electrolyte, P(VDF-TrFE) polymer has an all-trans conformation, in which all fluorineatoms locate on one side of the polymer chain, providing fast Li^(+) transporthighways. Meanwhile, the LDH can immobilize the anions of Li salts based onthe electrostatic interactions, promoting the dissociation of Li salts, therebyenhancing the ionic conductivity (6.4 × 10^(-4) S cm^(-1)) and Li^(+) transferencenumber (0.76). The anion immobilization effect can realize uniform electricfield distribution at the anode surface and suppress the dendritic Li growth.Moreover, the hydrogen bonding interaction between LDH and polymerchains also endows the composite electrolyte with strong mechanical properties.Thus, at room temperature, the Li jj Li symmetric cells can be stablycycled over 1000 h at a current density of 0.2 mA cm^(-2), and the full cells withLiFePO_(4) cathode deliver a high capacity retention (>95%) after 200 cycles. This work offers a promising route to construct solid-state polymer electrolytes withfast Li^(+) transport.

智能视频监控关键技术:行人再识别研究综述

行人再识别(person re-identification,ReID)旨在解决跨摄像头跨场景下目标行人的关联与匹配,作为智能视频监控系统的关键环节,对维护社会公共秩序具有重大作用.为了深入了解行人再识别研究现状和加速推进国内行人再识别相关研究及技术落地,本文对该领域国家自然科学基金申报数量、资助力度以及地理分布情况进行统计,并针对近年来发表在国际顶级会议和期刊上的行人再识别研究进行全面梳理.具体地,首先阐述一个标准行人再识别算法流程,并总结其中3个关键技术:表征学习、度量学习和重排序优化.随后,列举了实际开放场景中面临的主要难点与挑战,并据此概括了7种开放行人再识别任务:遮挡、无监督、半监督、跨模态、场景行人搜索、对抗鲁棒和快速检索.此外,本文整理了标准行人再识别和开放行人再识别的代表性数据集,并且对一些代表性行人再识别算法进行比较.最后本文对行人再识别的未来发展趋势进行展望.

基于纳米载体的多柔比星耐药干预及提高抗肿瘤效果的研究进展

肿瘤多药耐药(MDR)是指肿瘤细胞长期接触某一化疗药物,对多种化疗药物产生交叉耐药性。这是肿瘤细胞免受化疗药物攻击最重要的防御机制,也是导致化疗失败的主要原因。纳米载体作为一种潜在的药物递送工具,可以通过增加药物靶向性分布、实现药物选择性释放、提高细胞内摄、光化学结合以及协同递送多种活性分子等方式来实现对MDR模型的干预。笔者就纳米载体在对抗MDR方面的应用研究进行综述。

门控型药物递送系统研究进展

门控型药物递送系统,旨在通过门控基团使药物在正常生理条件下处于稳定包载状态。而在肿瘤等病变微环境或外源性因素刺激下,门控基团脱落或改变实现药物的响应性释放。本文主要针对刺激响应性连接臂和刺激响应性基团两个方面的应用,综述了近10年门控型药物递送系统的研究进展。

基于叶酸受体靶向的肿瘤诊断和治疗策略

叶酸受体(folate receptors,FRs)在人类多种癌症中过表达,如卵巢癌、肺癌、乳腺癌、脑癌等。而叶酸(folic acid,FA)是FRs的高亲和力配体,当与其他分子结合时,仍保留其受体结合特性。基于FRs的靶向技术已成功应用于叶酸受体阳性肿瘤的诊断和治疗中,且显著增强了对癌细胞的特异性和选择性。因此,基于FRs的靶向策略有望提高临床上相关抗癌药物的安全性和有效性。本文主要对基于FRs靶向的肿瘤诊断及治疗策略进行综述,特别关注这一领域的最新进展以及未来可能的发展方向。

YOLOP:You Only Look Once for Panoptic Driving Perception

A panoptic driving perception system is an essential part of autonomous driving.A high-precision and real-time perception system can assist the vehicle in making reasonable decisions while driving.We present a panoptic driving perception network(you only look once for panoptic(YOLOP))to perform traffic object detection,drivable area segmentation,and lane detection simultaneously.It is composed of one encoder for feature extraction and three decoders to handle the specific tasks.Our model performs extremely well on the challenging BDD100K dataset,achieving state-of-the-art on all three tasks in terms of accuracy and speed.Besides,we verify the effectiveness of our multi-task learning model for joint training via ablative studies.To our best knowledge,this is the first work that can process these three visual perception tasks simultaneously in real-time on an embedded device Jetson TX2(23 FPS),and maintain excellent accuracy.To facilitate further research,the source codes and pre-trained models are released at https://github.com/hustvl/YOLOP.

基于深度学习的场景文字检测与识别

场景文字检测与识别是一种通用文字识别技术,已成为近年来计算机视觉与文档分析领域的热点研究方向.其被广泛应用于地理定位、车牌识别、无人驾驶等领域.相对于传统的文档文字检测和识别,场景文字在字体、尺度、排布、背景等方面变化更加剧烈,深度学习技术也由于卓越的性能成为该领域的主流方法.本文主要回顾了作者基于深度学习在此领域取得的代表性成果,并对此领域未来研究趋势进行了展望.

Scene text detection and recognition： recent advances and future trends

Text, as one of the most influential inventions of humanity, has played an important role in human life, so far from ancient times. The rich and precise information embod- ied in text is very useful in a wide range of vision-based ap- plications, therefore text detection and recognition in natu- ral scenes have become important and active research topics in computer vision and document analysis. Especially in re- cent years, the community has seen a surge of research efforts and substantial progresses in these fields, though a variety of challenges （e.g. noise, blur, distortion, occlusion and varia- tion） still remain. The purposes of this survey are three-fold： 1） introduce up-to-date works, 2） identify state-of-the-art al- gorithms, and 3） predict potential research directions in the future. Moreover, this paper provides comprehensive links to publicly available resources, including benchmark datasets, source codes, and online demos. In summary, this literature review can serve as a good reference for researchers in the areas of scene text detection and recognition.

Correction to:YOLOP:You Only Look Once for Panoptic Driving Perception

Correction to:YOLOP:You Only Look Once for Panoptic Driving Perception DOI:10.1007/s11633-022-1339-y Authors:Dong Wu,Man-Wen Liao,Wei-Tian Zhang,Xing-Gang Wang,Xiang Bai,Wen-Qing Cheng,Wen-Yu Liu The article YOLOP:You Only Look Once for Panoptic Driving Perception,written by Dong Wu,Man-Wen Liao,Wei-Tian Zhang,Xing-Gang Wang,Xiang Bai,Wen-Qing Cheng,Wen-Yu Liu,was originally published without Open Access.

基于光动力疗法消融肿瘤的无机纳米材料研究进展

光动力疗法(photodynamic therapy,PDT)是一种微创消融肿瘤的新手段。这种手段的优势是可以在对正常组织和器官产生最小副作用的情况下抑制肿瘤。近年来,将纳米粒子与光敏剂组合作为介导PDT的治疗制剂,在肿瘤治疗领域显示出了明显优势。在这方面,金、磁性氧化铁、石墨烯纳米颗粒及其他无机纳米材料引起了人们的关注。这些材料与光敏剂以复合纳米粒的形式结合,降低了体内外正常组织的细胞毒性,改善了其在生物环境中的溶解度,提高了治疗效果。笔者介绍了PDT的基本原理,并总结了以上无机复合纳米材料在PDT中的应用,以期为构建更合理、更有效的整合无机纳米粒的光动力治疗平台提供参考。

Information processing for unmanned aerial vehicles(UAVs)in surveying,mapping,and navigation

Unmanned Aerial Vehicles(UAVs)have been involved in a wide range of remote sensing applications.In particular,recent developments in robotics,computer vision,and geomatics technologies have made it possible to capture a huge amount of visual data with low-cost UAVs.As a kind of rapid,flexible and low-cost data acquisition system,UAVs have shown great potential to perform numerous surveying,mapping.

Directional Edge Boxes： Exploiting Inner Normal Direction Cues forEffective Obiect Prooosal Generation

Edges are important cues for localizing object proposals. The recent progresses to this problem are mostly driven by defining effective objectness measures based on edge cues. In this paper, we develop a new representation named directional edges on which each edge pixel is assigned with a direction toward object center, through learning a direction prediction model with convolutional neural networks in a holistic manner. Based on directional edges, two new objectness measures are designed for ranking object proposals. Experiments show that the proposed method achieves 97.1% object recall at an overlap threshold of 0.5 and 81.9% object recall at an overlap threshold of 0.7 at 1 000 proposals on the PASCAL VOC 2007 test dataset, which is superior to the state-of-the-art methods.