Metabolic Glycoengineering in hMSC-TERT as a Model for Skeletal Precursors by Using Modified Azide/Alkyne Monosaccharides

Metabolic glycoengineering enables a directed modification of cell surfaces by introducing target molecules to surface proteins displaying new features. Biochemical pathways involving glycans differ in dependence on the cell type; therefore, this technique should be tailored for the best results. We characterized metabolic glycoengineering in telomerase-immortalized human mesenchymal stromal cells (hMSC-TERT) as a model for primary hMSC, to investigate its applicability in TERT-modified cell lines. The metabolic incorporation of N-azidoacetylmannosamine (Ac₄ManNAz) and N-alkyneacetylmannosamine (Ac₄ManNAl) into the glycocalyx as a first step in the glycoengineering process revealed no adverse effects on cell viability or gene expression, and the in vitro multipotency (osteogenic and adipogenic differentiation potential) was maintained under these adapted culture conditions. In the second step, glycoengineered cells were modified with fluorescent dyes using Cu-mediated click chemistry. In these analyses, the two mannose derivatives showed superior incorporation efficiencies compared to glucose and galactose isomers. In time-dependent experiments, the incorporation of Ac₄ManNAz was detectable for up to six days while Ac₄ManNAl-derived metabolites were absent after two days. Taken together, these findings demonstrate the successful metabolic glycoengineering of immortalized hMSC resulting in transient cell surface modifications, and thus present a useful model to address different scientific questions regarding glycosylation processes in skeletal precursors.     

红心火龙果发酵液喷雾干燥工艺优化及红心火龙果籽油的研究

以红心火龙果发酵液作为研究对象,通过优化喷雾干燥工艺制备粉剂,最佳工艺条件为:20%麦芽糊精,进液量:10mL/min,进口温度为120℃,出口温度为65℃;得到的粉剂为紫红色粉末,益生菌含量达到108cfu/g以上,口感酸甜。将发酵后的火龙果籽进行提取,得到的火龙果籽油含有丰富的十六酸、亚油酸和油酸。     

Photomemory and Pulse Monitoring Featured Solution-Processed Near-Infrared Graphene/Organic Phototransistor with Detectivity of 2.4 × 1013 Jones

Emerging graphene/organic phototransistors are eye-catching technologies owing to their unique merits including easy/low-cost fabrication, temperature independent, and achieving various functions. However, their development in the near-infrared (NIR) region is experiencing a bottleneck of inferior sensitivity due to low exciton dissociation efficiency and inefficient charge extraction rate. Here, a novel-design solution-processed graphene/organic NIR phototransistor is reported, that is, creatively introducing electron extraction layer of ZnO on graphene channel and employing organic ternary bulk heterojunction as photosensitive layer, successfully breaking that bottleneck. The phototransistor exhibits a high responsivity of 6.1 × 10⁶ A W⁻¹, a superior detectivity of 2.4 × 10¹³ Jones, and a remarkable minimum detection power of 1.75 nW cm⁻² under 850 nm radiation. Considering its excellent NIR detection performance, a noncontact transmission-type pulse monitoring is carried out with no external circuit support, from which human pulse signal and heart rate can be displayed in real time. The phototransistor, interestingly, can be switched into a photomemory function with a retention time of 1000 s in the atmosphere through a gate voltage of −20 V. The design takes the characteristics of graphene/organic phototransistors to a higher level, beyond the limit of sensitivity, and opens up a novel approach for developing multifunction devices.     

基于秩序与非秩序理论的文创产品卡通形象设计研究

目的 从秩序与非秩序理论出发,研究文创产品卡通形象的设计方法.方法 对秩序与非秩序理论的视觉机制和创制理论进行梳理,结合实例,阐述了其与文创产品卡通形象设计之间的联系,分析文创产品卡通形象中的秩序与非秩序的表现形式,提出基于秩序与非秩序理论文创产品卡通形象设计的主要原则,归纳出一套基于秩序与非秩序理论的文创产品卡通形象设计流程与方法,指导设计实践,并验证这些理论方法在设计实践中有效性与可行性.结论 通过对秩序与非秩序理论的研究,文创产品卡通形象设计时应注意提高辨识度、亲和力和便于衍生设计的原则.探索基于秩序与非秩序理论的设计流程与方法,按照界定主题、主体形象设计、主体形象拓展、衍生品应用四个环节开展整体方案设计,为文创产品卡通形象设计提供新的思路与方法.     

木质纤维与水泥共同改良软土的力学性能与微观机制分析

通过压实试验、无侧限抗压强度试验和劈裂试验,分析不同木质纤维含量、水泥含量和固化时间对软土力学性能的影响规律,探讨木质纤维、水泥改良软土的微观机制。结果表明,木质纤维的加入对水泥改良软土的击实特性有显著的影响;木质纤维与水泥可有效改善土体的抗压和劈裂抗拉强度,随着木质纤维含量的增加,改良土的抗压和劈裂抗拉强度呈现出明显的“驼峰”现象,并在木质纤维含量为0.25%时最大;木质纤维与水化产物、软土颗粒形成互锁效应,增大了改良土的摩擦力,同时木质纤维还承担一定的拉伸强度,使改良土的劈裂强度增加。     

煤化工酸水汽提装置运行存在问题及解决方法

本文简述了酸水汽提工艺的发展概况和技术进展,详细介绍了煤化工酸水汽提装置实际运行中存在的几类主要问题,并提出切实可行的解决措施,具有一定的借鉴意义。     

Effect of Newtonian heating/cooling on free convection in an annular permeable region in the presence of heat source/sink

The influence of Newtonian heating/cooling in the presence of heat source/sink has been investigated on laminar free convective flow in a vertical annular permeable region. The mathematical model for the problem has been considered as a boundary value problem consisting of two simultaneous ordinary differential equations. The boundary value problem has been transformed to nondimensional form. This has given rise to a number of parameters representing both geometrical and physical features of the problem. Closed‐form analytical solutions of the governing equations have been obtained for two different cases of internal heat generation/absorption. To assess the effects of governing parameters on the fluid velocity and temperature, a number of profiles of these field variables have been presented. The efficacy of the distinct processes on the field variables has been discussed extensively. The main outcome obtained in this study is that the velocity as well as temperature is enhanced in the case of the Newtonian heating while the opposite behavior occurs in the Newtonian cooling for both cases of source and sink. Furthermore, the influence of the governing parameters has been shown on the skin friction, volume flow rate, and the Nusselt number.     

液体饮料PET无菌灌装工艺与装备研发进展

文章对目前液体饮料PET无菌灌装工艺与装备进行了归纳与总结，并对其研发趋势进行了展望，以期为液体饮料生产中PET无菌灌装技术的应用及优化提供相关依据。     

道路用聚氨酯改性沥青的制备工艺探讨

结合不同改性剂掺量单因素试验,确定了采用88mm叶轮、115mm容器、圆盘锯齿式搅拌器(转速1400r/min)、175℃共混温度、改性剂掺量4.27%、单次搅拌300g的制备工艺参数。在此条件下制备的聚氨酯改性沥青具有优异的水稳定性、储存稳定性且耐老化、耐高温,拥有比普通聚合物改性沥青更高的车辙因子G*/sinδ和15℃动态模量,基本满足高模量沥青要求。     

Quaternäre Metall/Metalloxid‐Katalysatoren als Wandkatalysatoren in Mikroreaktoren für Power‐to‐Gas‐Applikationen mittels kombinatorischer Hochdurchsatzmethoden

Catalysts of quaternary composition have been prepared and tested for the Sabatier process. For catalyst syntheses the following techniques have been used: sol‐gel methods, wet impregnation and incipient wetness impregnation. The Sabatier reaction was carried out at temperatures between 520 K and 670 K, pressures of 15 bar and 30 bar using a mixture H₂:CO₂ of 4:1. Activity screening of the microscale wall catalysts was performed by a custom‐built 10‐fold parallel gas‐flow microreactor setup in sequential operating mode. To analyze the gas phase compositions GC‐FID was used.