The Dial-a-Ride Problem (DARP): Variants,modeling issues and algorithms

The Dial-a-Ride Problem (DARP) consists of designing vehicle routes and schedules for n users who specify pick-up and drop-off requests between origins and destinations. The aim is to plan a set of m minimum cost vehicle routes capable of accommodating as many users as possible, under a set of constraints. The most common example arises in door-to-door transportation for elderly or disabled people. The purpose of this article is to review the scientific literature on the DARP. The main features of the problem are described and classified and some modeling issues are discussed. A summary of the most important algorithms is provided.AMS classification: 90B06, 90C27, 90C59     

A Framework for MPEG‐4 Contents Delivery over DMB

Digital Multimedia Broadcasting (DMB) is an upcoming standard in Korea used to provide mobile multimedia broadcasting service based on the Eureka‐147 Digital Audio Broadcasting (DAB) system. The current dominant multimedia coding standard, MPEG‐4, is foreseen to play an important role in forthcoming DMB services. However, the current approaches for transporting MPEG‐4 content over DMB networks are not optimized. To address this issue we propose a novel MPEG‐4 stream multiplexer, called M4SMux, which provides better stream multiplexing and delivery over DMB networks. M4SMux features an MPEG‐4 elementary‐stream interleaving mechanism that reduces the multiplexing overhead and a multiplex configuration mechanism that utilizes M4SLinkTable for easy content access. In addition, we propose an error correction method which enhances transport efficiency.     

CACTSE：基于云片式多终端协同服务环境的移动近场内容分发

Along with the rapid development of communications, the Internet, and smart terminals, mobile Internet has become a hot topic with both opportunities and challenges. In this article, a new perspective on edge content delivery service for mobile Internet is described, based on cooperating terminals. A mobile cloud architecture named Cloudlet Aided Cooperative Terminals Service Environment (CACTSE) is proposed as an edge network service environment. The Service Manager (SM), a cloudlet like module, is introduced into the local service domain in order to manage the in-domain terminals and help coordinate the content delivery requests for better bandwidth efficiency as well as user experience. The reference model is presented in this article with architecture and mechanism design. Moreover, the research progress and potential technology trends of CACTSE are analysed based on the related R&D directions.     

Delivery Techniques for Enhancing CAR T Cell Therapy against Solid Tumors

Chimeric antigen receptor (CAR) T cells exhibit promising results for cancer immunotherapy. However, the clinical success is still restricted to certain types of blood cancers, while in solid tumors the clinical activity is modest and potential toxicities remain a concern. There are various barriers that prevent CAR T cells from combating solid tumors. Therefore, distinct strategies have been explored to augment CAR T cell proliferative capacity, persistence, and effector function. Altering the tumor microenvironment, and in particular its physiochemical properties and immunosuppressive milieu, is of great significance to facilitate CAR T cell therapy. In this article, emerging strategies implemented to overcome the barriers of CAR T cell therapy in solid tumors are reviewed. Enhancing infiltration, activation, and persistence of CAR T cells has been addressed in several preclinical models. The future development of this field to promote innovation and clinical translation is also discussed.     

Aminoglycoside-Based Biomaterials: From Material Design to Antibacterial and Gene Delivery Applications

Aminoglycosides are a family of naturally isolated or chemically semi-synthesized antibiotics consisting of aminocyclitols with several amino and saccharide units. The unique molecule structures render aminoglycosides promising building blocks with high reactivity to perform various non-covalent and covalent reactions, and they are further employed to rationally fabricate versatile materials, such as hydrogels, amphiphiles, hyperbranched polymers, biointerfaces, and nanoparticles. Despite aminoglycosides are widely used in clinics to treat bacterial infections, almost all the efforts are focused on molecular modifications to reduce their toxicities and overcome antibiotic resistance, while their actions as building blocks to construct biomaterials are scarcely discussed. In this feature article, the current progress on the rational design, emergent properties, and promising biological applications of aminoglycoside-based biomaterials are summarized. It is believed that this paper may provide guidance to develop new biomaterials using natural functional molecules as building blocks, and start a new life of aminoglycosides from the view of materials science.     

A comprehensive theoretical evaluation of the end-to-end performance of SoftCast-based linear video delivery schemes

SoftCast-based linear video delivery (LVD) schemes have been proposed as an alternative to traditional video transmission schemes in wireless error-prone environments. The end-to-end performance of SoftCast-based schemes have been evaluated in Xiong et al. (2016), where a theoretical model based on the Peak Signal-to-Noise Ratio (PSNR) metric has been proposed. The latter is limited to the use of a Zero-Forcing (ZF) estimator at the receiver side, and does not consider bandwidth restrictions. Nevertheless, bandwidth restrictions are common and necessary in practice, especially when considering the transmission of video content. It is mandatory to take this aspect into consideration as it may drastically influence the received video quality. In this paper, we provide valid and significant extensions of the initial model. In total, three models are introduced taking into account both (1) bandwidth constraints (i.e., data compression applied), (2) the use of a Linear Least Square Error (LLSE) estimator instead of the ZF one as well as (3) the use of the optimal power allocation. We show that regardless of the bandwidth reduction applied, the type of estimator as well as the power allocation used, the end-to-end video quality can be accurately modeled and predicted at the transmitter according to the video content characteristics, the type of estimator used at the receiver and the channel conditions. The validity of these three models is assessed through extensive end-to-end simulations. These new models give solid theoretical guidelines for optimizing and studying the performance of linear video delivery schemes.     

4D Printing of a Bioinspired Microneedle Array with Backward‐Facing Barbs for Enhanced Tissue Adhesion

Microneedle (MN), a miniaturized needle with a length‐scale of hundreds of micrometers, has received a great deal of attention because of its minimally invasive, pain‐free, and easy‐to‐use nature. However, a major challenge for controlled long‐term drug delivery or biosensing using MN is its low tissue adhesion. Although microscopic structures with high tissue adhesion are found from living creatures in nature (e.g., microhooks of parasites, barbed stingers of honeybees, quills of porcupines), creating MNs with such complex microscopic features is still challenging with traditional fabrication methods. Here, a MN with bioinspired backward‐facing curved barbs for enhanced tissue adhesion, manufactured by a digital light processing 3D printing technique, is presented. Backward‐facing barbs on a MN are created by desolvation‐induced deformation utilizing cross‐linking density gradient in a photocurable polymer. Barb thickness and bending curvature are controlled by printing parameters and material composition. It is demonstrated that tissue adhesion of a backward‐facing barbed MN is 18 times stronger than that of barbless MN. Also demonstrated is sustained drug release with barbed MNs in tissue. Improved tissue adhesion of the bioinspired MN allows for more stable and robust performance for drug delivery, biofluid collection, and biosensing.     

几种人体生物特征的生物识别技术比较

随着社会公共安全和个人的自身信息安全要求的提高,生物识别技术成为了安全验证的首选方式,他是利用人体生物特征对人进行身份识别的一种高科技技术。简要介绍了生物识别技术出现的背景、生物识别技术的概念、生物识别的基本过程、生物识别技术的发展动态及前景。对当前比较流行的几种生物识别技术指纹识别、虹膜识别、视网膜识别、面部识别、签名识别、声音识别、基因识别等从原理及其特点上予以了论述和比较。     

Site‐Selectively Coated,Densely‐Packed Microprojection Array Patches for Targeted Delivery of Vaccines to Skin

Densely packed dry‐coated microprojections are shown to deliver vaccines to targeted locations within the skin that are rich in immune cells, thus inducing protective immune responses against a lethal virus challenge. Selectively limiting the antigen coating to the tips of the projections, which penetrate the skin, would significantly reduce the amount of vaccine required in immunization. In this paper a simple technique, dip‐coating the microprojections, is introduced to meet this goal. By increasing the coating solution viscosity, an otherwise strong capillary action is mitigated and the desired controlled coating length on projections is achieved. Following application to the skin, most of the coated vaccine material is rapidly released from the projections (82.6% in mass within 2 min) to the target locations within the skin strata and a potent immune response is induced when a conventional influenza vaccine (Fluvax) is tested in a mouse model. The utility of this coating approach to a variety of molecules representative of vaccines (e.g., chicken egg ovalbumin (OVA) protein, DNA, and fluorescent dyes) is demonstrated. These collective attributes, together with the simplicity of the approach, position the dip‐coating method for practical utility in large vaccination campaigns.