207 research outputs found

    Leveraging IS-based Energy Systems for Energy Poverty Alleviation in Zambia: An Interpretive Case Study

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    Energy poverty is a pressing societal challenge, affecting over 700 million people worldwide, particularly underserved communities. Although information systems (IS) resources have been made available to alleviate energy poverty, realizing their effective use for intended impacts remains challenging. In this ongoing research, we adopt a resourcing perspective to explore how IS resources can be effectively used to alleviate energy poverty in underserved contexts. We present a community case study in Lusaka, Zambia, where the effective use of IS-based Energy Systems (IES) has yielded promising results. We develop an initial framework that explains “what it takes” to realize effective IES resourcing for energy poverty alleviation, including mechanisms (i.e., gap spotting, narratives, and scaffolding) and actors (i.e., resource providers and users) in three stages - resourcing IN, resourcing WITHIN, and resourcing OUT. We also indicate the next steps of this study and expected contributions and discuss implications for future research

    Coupling of RF Antennas to Large Volume Helicon Plasma

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    Large volume helicon plasma sources are of particular interest for large scale semiconductor processing, high power plasma propulsion and recently plasma-material interaction under fusion conditions. This work is devoted to studying the coupling of four typical RF antennas to helicon plasma with infinite length and diameter of 0.50.5~m, and exploring its frequency dependence in the range of 13.567013.56-70~MHz for coupling optimization. It is found that loop antenna is more efficient than half helix, Boswell and Nagoya III antennas for power absorption; radially parabolic density profile overwhelms Gaussian density profile in terms of antenna coupling for low-density plasma, but the superiority reverses for high-density plasma. Increasing the driving frequency results in power absorption more near plasma edge, but the overall power absorption increases with frequency. Perpendicular stream plots of wave magnetic field, wave electric field and perturbed current are also presented. This work can serve as an important reference for the experimental design of large volume helicon plasma source with high RF power

    Exploring the active mechanism of berberine against HCC by systematic pharmacology and experimental validation

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    This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.Berberine (BBR) is the main component of Coptidis rhizoma, the dried rhizome of Coptis chinensis and is a potential plant alkaloid used for the treatment of cancer due to its high antitumor activity. The present study examined the therapeutic potential and molecular mechanism of action of BBR against HCC, using systematic pharmacology combined with a molecular docking approach and experimental validation in vitro. Through systematic pharmacological analysis, it was found that BBR serves a significant role in inhibiting HCC by affecting multiple pathways, especially the PI3K/AKT signaling pathway. Furthermore, the docking approach indicated that the binding of BBR to AKT could lead to the suppression of AKT activity. The present study examined the inhibitory effect of BBR on the PI3K/AKT pathway in HCC and identified that BBR downregulated the expressions of phosphorylated AKT and PI3K in MHCC97‑H and HepG2 cells, inhibiting their growth, cell migration and invasion in a dose‑dependent manner. In addition, inhibition of the AKT pathway by BBR also contributed to cell apoptosis in MHCC97‑H and HepG2 cells. Taken together, the results of the present study suggested that BBR may be a promising antitumor drug for HCC that acts by inhibiting the PI3K/AKT pathway

    Construction of acellular cartilage matrix/silk fibroin scaffold and its cartilage tissue engineering study

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    Objective·To construct a bioactivity tissue engineering scaffold with double network cross-linking for cartilage tissue regeneration using an acellular cartilage matrix (ACM) with a natural silk fibroin (SF) biomaterial.Methods·The cell-associated immunogenic components were removed by nuclease digestion, and the extracellular matrix-associated glycoproteins and collagen structures were retained, The efficiency of cartilage tissue decellularization was measured by spectrophotometry by using DNA, histoglycosaminoglycan and collagen quantification kits. ACM and SF were configured into a mixed solution, and the nucleophilic cross-linking reaction with the hydroxyl and carboxyl groups contained in both was carried out by adding ethylene glycol diglycidyl ether. Then it was freeze-dried to make porous bionic scaffolds (n=5). At the same time, porous scaffolds containing only ACM or SF were prepared by the same method (n=5). The microstructure of the scaffolds was observed by scanning electron microscopy (SEM), and the mechanical strength, elastic modulus and resilience of different groups of scaffolds were evaluated by mechanical tests. The internal and external nutrient exchange capacity of the scaffolds was reacted by water absorption rate. Chondrocytes from rabbit ears were isolated, cultured, and seeded on ACM-SF scaffolds. After 1, 4, and 7 days of culture, the adhesion, distribution, and matrix secretion of the cells on the scaffolds were observed by SEM, and the viability status of the cells was determined by double-staining of live and dead cells. CCK-8 method was used to determine the cytotoxicity of the scaffolds. The cells were implanted subcutaneously in nude mice, cultured in vivo for 4 and 8 weeks, and finally removed for histological testing. Differences between groups were tested by One-Way ANOVA. Statistical significance was accepted at a value of P<0.05.Results·After enzymatic digestion, almost no cells remained in the acellular matrix, and the active components of the extracellular matrix were retained. The composite scaffold prepared by ACM-SF has interconnected microporous structure and good elasticity, and could recover its original shape after repeated compression in the wet state. The water absorption rate of ACM-SF reached nearly 20 times, which provided an effective material exchange condition for the cell adhesion environment. Histological tests showed that the ACM-SF scaffold regenerated homogeneous, typical cartilage tissue in vivo.Conclusion·ACM-SF composite porous scaffold has a good bionic microenvironment and can be applied to tissue engineering cartilage regeneration
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