86 research outputs found

    A Study on the Impact of Urban Digitalization on the Urban-rural Income Gap

    Get PDF
    The empirical research topic for this paper is a panel dataset of 31 provinces and urban areas from my country from 2011 to 2020. On the one hand, it gauges the level of regional digital economic development. On the other side, we’ll talk about the structural impact of the level of digitalization on the urban-rural income difference and further debate whether the digital economy helps close or widen this gap. The findings show that the degree of digitization has a significant impact on reducing the income gap between urban and rural areas, while an increase in the Internet coverage index helps do so. However, the overall impact makes the digital economy unfavorable to reducing the income gap between urban and rural areas

    3DICE coding matrix multidirectional macro-architecture modulates cell organization, shape, and co-cultures endothelization network

    Get PDF
    Natural extracellular matrix governs cells providing biomechanical and biofunctional outstanding properties, despite being porous and mostly made of soft materials. Among organs, specific tissues present specialized macro-architectures. For instance, hepatic lobules present radial organization, while vascular sinusoids are branched from vertical veins, providing specific biofunctional features. Therefore, it is imperative to mimic such structures while modeling tissues. So far, there is limited capability of coupling oriented macro-structures with interconnected micro-channels in programmable long-range vertical and radial sequential orientations. Herein, a three-directional ice crystal elongation (3DICE) system is presented to code geometries in cryogels. Using 3DICE, guided ice crystals growth templates vertical and radial pores through bulky cryogels. Translucent isotropic and anisotropic architectures of radial or vertical pores are fabricated with tunable mechanical response. Furthermore, 3D combinations of vertical and radial pore orientations are coded at the centimeter scale. Cell morphological response to macro-architectures is demonstrated. The formation of endothelial segments, CYP450 activity, and osteopontin expression, as liver fibrosis biomarkers, present direct response and specific cellular organization within radial, linear, and random architectures. These results unlock the potential of ice-templating demonstrating the relevance of macro-architectures to model tissues, and broad possibilities for drug testing, tissue engineering, and regenerative medicine.The authors are grateful for the Portuguese Foundation for Science and Technology (FCT) distinction attributed to R. F. Canadas (SFRH/ BD/92565/2013), and to J. M. Oliveira (IF/00423/2012, IF/01285/ 2015). R. F. Canadas is also thankful to FCT, Fundo Europeu de Desenvolvimento Regional (FEDER), and Programa Operacional Competitividade e Internacionalizaç˜ao (POCI) for funding the B-Liver Project (PTDC/EMD-EMD/29139/2017). The authors are also thankful to FCT for supporting the project Hierarchitech (M-ERA-NET/0001/2014) and for the funds provided under the 3 BioMeD project (JICAM/0001/2017). The authors acknowledge that this material and collaboration is based in part upon work supported by Luso-American Development Foundation (FLAD), 2016/CON15/CAN6). U. Demirci is also grateful for the Canary Center at Stanford for Cancer Early Detection Seed Award. The authors are also grateful for the support provided by Diana Bicho and Nicolas Cristini on scaffold characterization and cell culture, respectively

    Molecular mimetic self-assembly of colloidal particles

    No full text
    This article presents an overview of the current progress in molecular mimetic self-assembly of colloidal particles. Firstly, the recent study of colloidal particles at interfaces is highlighted, underlining the mesoscopic mimicry of the surface activity of amphiphilic molecules using colloidal particles. Secondly, various strategies developed thus far to impart colloidal particles with anisotropy in terms of chemical composition, surface chemistry and particle morphology, which are regarded as mesoscopic atoms and molecules, are reviewed. Thirdly, an overview of the current theoretical and experimental results of using the rules of molecular synthesis and selfassembly to direct self-assembly of colloidal particles is presented. Finally, the experimental challenges associated with molecular mimetic self-assembly of colloidal particles are outlined, giving a rather conservative conclusion of the status quo of this new research field with a very optimistic outlook.

    Control over the Gradient Differentiation of Rat BMSCs on a PCL Membrane with Surface-Immobilized Alendronate Gradient

    No full text
    Gradient biomaterials can offer progressively changing signals to specific tissue interface, and thereby modulate the conjunction between different tissues. A linear density gradient of alendronate (Aln), a molecule that is capable of promoting osteogenic differentiation of bone mesenchymal stem cells (BMSCs), was created on an aminolyzed poly­(ε-caprolactone) (PCL) membrane. X-ray photoelectron spectroscopy and quartz crystal microbalance with dissipation revealed the linear increase of the Aln amount as a function of the position on the PCL membrane. By contrast, the surface wettability and energy were kept unchanged. The surface-grafted Aln showed a stronger ability to induce the osteogenic differentiation of rat BMSCs than its counterpart in culture medium of the same amount, and the osteo-inductive culture medium. On the Aln-grafted gradient surface, the BMSCs showed gradient osteogenic differentiation as a function of membrane position in terms of cell morphology, alkaline phosphatase activity, calcium deposition, and the expression of osteogenesis marker proteins including collagen type I (COL I), Runt-related transcription factor 2 (Runx2), and osteocalcin (OCN)

    Numerical analysis on the modal characteristics of a pumped storage unit runner in cavitating flow

    No full text
    Cavitation is an important issue in pumped storage unit as it can compromise the safe and stable operation of the unit. The present work aims revealing the dynamic behavior of a pump-turbine runner in cavitating flow from a perspective of fluid-structure interaction. A procedure is developed to map the cavities from computation fluid dynamics simulation to finite element model. The calculated flow rate and head agree well with experimental results. A nonlinear relationship between the sonic speed in cavity and vapor volume fraction is applied in the finite element model. The effect of the sonic speed and fluid density on the dynamic behavior of the runner, and their coupled effect are investigated, respectively. Then the modal characteristics of the runner in cavitating flow are analyzed by solving the first 8000 modes, and a harmonic analysis is carried out to determine the main global mode. The results show that the sonic speed (20 m/s–100 m/s) could have a greater effect than the added mass for some modes. Finally, it is shown that the complexity and number of nodal diameter modes greatly increases in cavitating flow, with a lot of local modes which are similar to global nodal diameter mode. This work provides a method for evaluating the dynamic behavior of the pump-turbine runner in cavitating flow and could contribute to the safe operation of the pump-turbine unit.Peer ReviewedPostprint (published version

    Genetically Engineered Cellular Nanovesicle as Targeted DNase I Delivery System for the Clearance of Neutrophil Extracellular Traps in Acute Lung Injury

    No full text
    Abstract Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) are prevalent critical illnesses with a high mortality rate among patients in intensive care units. Neutrophil extracellular traps (NETs) are implicated in the pathogenesis of ALI/ARDS and represent a promising therapeutic target. However, the clinical application of deoxyribonuclease I (DNase I), the only drug currently available to clear NETs, is limited due to the lack of precise and efficient delivery strategies. Therefore, targeted delivery of DNase I to the inflamed lung remains a critical issue to be addressed. Herein, a novel biomimetic DNase I delivery system is developed (DCNV) that employs genetically and bioorthogonally engineered cellular nanovesicles for pulmonary NETs clearance. The CXC motif chemokine receptor 2 overexpressed cellular nanovesicles can mimic the inflammatory chemotaxis of neutrophils in ALI/ARDS, leading to enhanced lung accumulation. Furthermore, DNase I immobilized through bioorthogonal chemistry exhibits remarkable enzymatic activity in NETs degradation, thus restraining inflammation and safeguarding lung tissue in the lipopolysaccharide‐induced ALI murine model. Collectively, the findings present a groundbreaking proof‐of‐concept in the utilization of biomimetic cellular nanovesicles to deliver DNase I for treating ALI/ARDS. This innovative strategy may usher in a new era in the development of pharmacological interventions for various inflammation‐related diseases
    corecore