A Role for Human Renal Tubular Epithelial Cells in Direct Allo-Recognition by CD4+ T-Cells and the Effect of Ischemia-Reperfusion

Direct allorecognition is the earliest and most potent immune response against a kidney allograft. Currently, it is thought that passenger donor professional antigen-presenting cells (APCs) are responsible. Further, many studies support that graft ischemia-reperfusion injury increases the probability of acute rejection. We evaluated the possible role of primary human proximal renal tubular epithelial cells (RPTECs) in direct allorecognition by CD4+ T-cells and the effect of anoxia-reoxygenation. In cell culture, we detected that RPTECs express all the required molecules for CD4+ T-cell activation (HLA-DR, CD80, and ICAM-1). Anoxia-reoxygenation decreased HLA-DR and CD80 but increased ICAM-1. Following this, RPTECs were co-cultured with alloreactive CD4+ T-cells. In T-cells, zeta chain phosphorylation and c-Myc increased, indicating activation of T-cell receptor and co-stimulation signal transduction pathways, respectively. T-cell proliferation assessed with bromodeoxyuridine assay and with the marker Ki-67 increased. Previous culture of RPTECs under anoxia raised all the above parameters in T-cells. FOXP3 remained unaffected in all cases, signifying that proliferating T-cells were not differentiated towards a regulatory phenotype. Our results support that direct allorecognition may be mediated by RPTECs even in the absence of donor-derived professional APCs. Also, ischemia-reperfusion injury of the graft may enhance the above capacity of RPTECs, increasing the possibility of acute rejection.     

The concept of smartness in cyber–physical systems and connection to urban environment

The next-generation systems are expected to be largely cyber–physical systems (CPSs) that autonomously control physical processes, through sensors and actuators typically in real-time feedback and cooperative control loops distributed among physical and cyber environments. The rapid technological advancements enhance the smartness of these CPSs, pushing their boundaries of performance and efficiency by embedding new information and communication technologies. However, to what extent CPSs should be smarter so that they do not compromise safety and security of safety critical systems? is an open research question. Towards this goal, the purpose of this study is to establish a grounded theory to analyse what makes these systems smart? and eventually, how to find a balance between smartness and safety risks? In this precinct, this article aims to develop a conceptual framework, define the dimensions and derive the characteristics that make CPSs smart. The proposed approach combines an automated informetric and systematic analysis of literature pertinent to the topic of smartness across anthropology, science, engineering and technology. The analysis of a case study building and the discussions presented herein support the connection between the existing understanding of CPSs and smartness offered by the building design approach in urban environment.     

Electrospun microporous gelatin–polycaprolactone blend tubular scaffold as a potential vascular biomaterial

The work reported involved the fabrication of an electrospun tubular conduit of a gelatin and polycaprolactone (PCL) blend as an adventitia‐equivalent construct. Gelatin was included as the matrix for increased biocompatibility with the addition of PCL for durability. This is contrary to most of the literature available for biomaterials based on blends of gelatin and PCL where PCL is the major matrix. The work includes the assiduous selection of key electrospinning parameters to obtain smooth bead‐free fibres with a narrow distribution of pore size and fibre diameter. Few reports elucidate the optimization of all electrospinning parameters to fabricate tubular conduits with a focus on obtaining homogeneous pores and fibres. This stepwise investigation would be unique for the fabrication of gelatin–PCL electrospun tubular constructs. The fabricated microfibrous gelatin–PCL constructs had pores of size ca 50–100 μm reportedly conducive for cell infiltration. The measured value of surface roughness of 57.99 ± 17.4 nm is reported to be favourable for protein adhesion and cell adhesion. The elastic modulus was observed to be similar to that of the tunica adventitia of the native artery. Preliminary in vitro and in vivo biocompatibility tests suggest safe applicability as a biomaterial. Minimal cytotoxicity was observed using MTT assay. Subcutaneous implantation of the scaffold demonstrated acute inflammation which decreased by day 15. The findings of this study could enable the fabrication of smooth bead‐free microfibrous gelatin–PCL tubular construct as viable biomaterial which can be included in a bilayer or a trilayer scaffold for vascular tissue engineering. © 2019 Society of Chemical Industry     

现场总线漫谈

从现场总线多标准的现状出发，阐述了控制对象多样性与技术多样性之间的必然联系，通过对目前现场总线与传统DCS应用现状的分析，对现场总线的发展和应用前景进行了展望。     

FF现场总线的网段负载能力的设计及计算

从生产安全运行的管理要求；电压压降和电流的限制及信号的衰减；网络运行时间的要求；系统设计的影响；备用能力的考虑等各个方面，结合上海赛科聚苯乙烯项目的具体设计，分析隔爆条件下FF现场总线的H1网段负载能力的设计，以供大家探讨。     

墙体裂缝的成因及防治

介绍了墙体裂缝的种类，从地基不均匀下沉、温度变化等方面分析了引起墙体裂缝的原因，介绍了墙体裂缝的预防措施和治理措施，以有效控制墙体裂缝的危害程度。     

双排桩门架—锚杆新型组合支护体系的应用研究

本文分析了双排桩门架支护结构的受力机理。针对工程实际进行变形分析,提出增设锚杆形成锚杆———双排桩门架式组合支护体系的方法,并与监测数据对比、验证。     

对CFG桩质量缺陷的探讨

根据具体工程的概况及水文地质条件，分析了CFG桩在地下水位出现大面积缩颈现象和复合地基载荷试验达不到设计要求的原因，并介绍了地基补强措施，以满足工程质量的要求。     

一种估算单桩经济直径的方法

在滩海油田开发过程中,经常需要设立立管桩,在环境荷载的作用下,立管桩顶部会发生位移,较大的位移对立管及栈桥的安全很不利,因此需要合理确定单桩的直径。埕岛油田在确定单桩直径时引入了经济直径的概念,文章对经济直径的原理进行了分析,给出了桩顶位移和桩径经济指数计算公式,并举例进行了计算,得出了桩径与桩顶位移及桩径经济指数的关系曲线, 进而求得经济桩径的取值范围。文章还对该方法的优缺点进行了分析。     

控制爆破在复杂基坑开挖中的应用

在紧邻厂房中控室的基坑开挖中，根据复杂环境条件与施工要求，采用浅孔微差爆破并通过选取合理开沟掏槽位置来控制最小抵抗线方向以及控制一次最大起爆药量等措施，达到了控制飞石、降低爆破地震的效果，保证了爆破质量与爆破安全，提高了施工效率。