The effect of dispersion state of graphene on mechanical properties of graphene/epoxy composites was investigated. The graphene sheets were exfoliated from graphite oxide (GO) via thermal reduction ...(thermally reduced GO, RGO). Different dispersions of RGO sheets were prepared with and without ball mill mixing. It was found that the composites with highly dispersed RGO showed higher glass transition temperature (Tg) and strength than those with poorly dispersed RGO, although no significant differences in both the tensile and flexural moduli are caused by the different dispersion levels. In particular, the Tg was increased by nearly 11°C with the addition of 0.2wt.% well dispersed RGO to epoxy. As expected, the highly dispersed RGO also produced one or two orders of magnitude higher electrical conductivity than the corresponding poorly dispersed RGO. Furthermore, an improved quasi-static fracture toughness (KIC) was measured in the case of good dispersion. The poorly and highly dispersed RGO at 0.2wt.% loading resulted in about 24% and 52% improvement in KIC of cured epoxy thermosets, respectively. RGO sheets were observed to bridge the micro-crack and debond/delaminate during fracture process due to the poor filler/matrix and filler/filler interface, which should be the key elements of the toughening effect.
•A new SVR model to forecast the demand response baseline for office buildings.•Take temperature two hours before DR event can improve the forecasting accuracy.•The forecasting accuracy is better ...than other seven existing methods in DR programs.•The model is very generic and can be applied to a wide variety of office buildings.
Demand Response (DR) aims at improving the operation efficiency of power plants and grids, and it constitutes an effective means of reducing grid risk during peak periods to ensure the safety of power supplies. One key challenge related to DR is the calculation of load baselines. A fair and accurate baseline serves as useful information for resource planners and system operators who wish to implement DR programs. In the meantime, baseline calculation cannot be too complex, and in most cases, only weather data input is permitted. Inspired by the strong non-linear capabilities of Support Vector Regression (SVR), this paper proposes a new SVR forecasting model with the ambient temperature of two hours before DR event as input variables. We use electricity loads for four typical office buildings as sample data to test the method. After analyzing the model prediction results, we find that the SVR model offers a higher degree of prediction accuracy and stability in short-term load forecasting compared to the other seven traditional forecasting models.
Sunitinib resistance is a major challenge for advanced renal cell carcinoma (RCC). Understanding the underlying mechanisms and developing effective strategies against sunitinib resistance are highly ...desired in the clinic. Here we identified an lncRNA, named lncARSR (lncRNA Activated in RCC with Sunitinib Resistance), which correlated with clinically poor sunitinib response. lncARSR promoted sunitinib resistance via competitively binding miR-34/miR-449 to facilitate AXL and c-MET expression in RCC cells. Furthermore, bioactive lncARSR could be incorporated into exosomes and transmitted to sensitive cells, thus disseminating sunitinib resistance. Treatment of sunitinib-resistant RCC with locked nucleic acids targeting lncARSR or an AXL/c-MET inhibitor restored sunitinib response. Therefore, lncARSR may serve as a predictor and a potential therapeutic target for sunitinib resistance.
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•lncARSR promotes sunitinib resistance and predicts poor response of RCC patients•Intercellular transfer of lncARSR by exosomes disseminates sunitinib resistance•lncARSR acts as a ceRNA for miR-34 and miR-449 to promote AXL and c-MET expression•Targeting lncARSR or AXL/c-MET in sunitinib-resistant RCC restores drug sensitivity
Qu et al. identify lncARSR as a mediator of sunitinib resistance in renal cell carcinoma by acting as a competing endogenous RNA for miR-34 and miR-449, thereby increasing expression of their targets AXL and c-MET, and show that exosome-mediated transmission of lncARSR can confer resistance to sensitive cells.
Summary
Objective
Intracranial aneurysm (IA) is a life threatening cerebrovascular disease characterized by phenotypic modulation of vascular smooth muscle cells (VSMCs) and loss of vessel cells. In ...addition to environmental factors, genetic factors have been proposed to be a critical factor in the onset and progression of IA. The present study investigates the effects of serine‐arginine protein kinase 1 (SRPK1) on VSMC proliferation and apoptosis both in vivo and in vitro, as well as its role in vascular remodeling in vivo through PI3 K/Akt signaling in IA.
Methods
Differentially expressed genes related to IA were initially identified using microarray analysis. Immunohistochemistry was conducted to determine SRPK1 expression in the vascular walls in IA and normal cerebral vascular walls. TUNEL staining were applied to observe cell apoptosis patterns of VSMCs. VSMC proliferation and apoptosis in vitro were detected by cell counting kit‐8 (CCK8) assay and flow cytometry. The expressions of SRPK1, PI3 K/Akt signaling pathway‐ and apoptosis‐related genes were evaluated by RT‐qPCR and Western blot analysis.
Results
Microarray data of GSE36791 and GSE54083 were analyzed to determine the selection of SRPK1 gene. The vascular walls in IA rat models produced high levels of SRPK1 expression and an activated PI3 K/Akt signaling pathway. VSMCs treated with siRNA‐SRPK1 exhibited enhanced cell proliferation, repressed cell apoptosis, and increased vascular remodeling, all of which suggest the inhibition of the PI3 K/AKT pathway. Notably, PI3 K/AKT pathway reversed the effect of SRPK1 silencing.
Conclusion
Our results show that siRNA‐mediated silencing of SRPK1 gene inhibits VSMC apoptosis, and increases VSMCs proliferation and vascular remodeling in IA via the PI3 K/Akt signaling pathway. Our findings provide a novel intervention target for the molecular treatment of IA.
Both the irreversible agglomeration of graphene sheets and poor sheet/matrix interface are obstacles to obtain the desired properties of graphene/polymer composites. Herein, we fabricated epoxy ...composites with highly dispersed graphene via a facile surfactant-assisted process, and investigated the correlations between surface modification, morphologies, dispersion, re-agglomeration behaviour and interfacial interaction of graphene and the corresponding thermal and mechanical properties of the composites. It is found that the surfactant treatments of graphene are effective to improve their dispersion stability in water and inhibit their re-agglomeration during the curing of resin. Scanning and transmission electron microscopy analysis demonstrates that the dispersion/exfoliation level of graphene in the composites is greatly improved after surface treatments. These above ameliorating effects along with improved interface between the matrix and graphene arising from the hydrophilic and hydrophobic molecules of non-ionic surfactant result in increased tensile properties compared with those without surface modification. Moreover, the thermal stability of the graphene/epoxy composites is slightly enhanced over that of neat epoxy.
The study of facile‐synthesis and low‐cost X‐ray scintillators with high light yield, low detection limit and high X‐ray imaging resolution plays a vital role in medical and industrial imaging ...fields. However, the optimal balance between X‐ray absorption, decay lifetime and excitonic utilization efficiency of scintillators to achieve high‐resolution imaging is extremely difficult due to the inherent contradiction. Here two thermally activated delayed fluorescence (TADF)‐actived coinage‐metal clusters M6S6L6 (M=Ag or Cu) were synthesized by simple solvothermal reaction, where the cooperation of heavy atom‐rich character and TADF mechanism supports strong X‐ray absorption and rapid luminescent collection of excitons. Excitingly, Ag6S6L6 (SC‐Ag) displays a high photoluminescence quantum yield of 91.6 % and scintillating light yield of 17420 photons MeV−1, as well as a low detection limit of 208.65 nGy s−1 that is 26 times lower than the medical standard (5.5 μGy s−1). More importantly, a high X‐ray imaging resolution of 16 lp/mm based on SC‐Ag screen is demonstrated. Besides, rigid core skeleton reinforced by metallophilicity endows clusters M6S6L6 strong resistance to humidity and radiation. This work provides a new view for the design of efficient scintillators and opens the research door for silver clusters in scintillation application.
High X‐ray absorption and thermally activated delayed fluorescence (TADF) properties jointly support hexanuclear cluster scintillators for high‐resolution imaging.
Diabetic nephropathy (DN) is the most common chronic kidney disease. Accumulation of glucose and metabolites activates resident macrophages in kidneys. Resident macrophages play diverse roles on ...diabetic kidney injuries by releasing cytokines/chemokines, recruiting peripheral monocytes/macrophages, enhancing renal cell injuries (podocytes, mesangial cells, endothelial cells and tubular epithelial cells), and macrophage-myofibroblast transition. The differentiation and cross-talks of macrophages ultimately result renal inflammation and fibrosis in DN. Emerging evidence shows that targeting macrophages by suppressing macrophage activation/transition, and macrophages-cell interactions may be a promising approach to attenuate DN. In the review, we summarized the diverse roles of macrophages and the cross-talks to other cells in DN, and highlighted the therapeutic potentials by targeting macrophages.
Toxoplasmosis is a zoonosis caused by Toxoplasma gondii (T. gondii). The current treatment for toxoplasmosis remains constrained due to the absence of pharmaceutical interventions. Thus, the pursuit ...of more efficient targets is of great importance. Lipid metabolism in T. gondii, including fatty acid metabolism, phospholipid metabolism, and neutral lipid metabolism, assumes a crucial function in T. gondii because those pathways are largely involved in the formation of the membranous structure and cellular processes such as division, invasion, egress, replication, and apoptosis. The inhibitors of T. gondii's lipid metabolism can directly lead to the disturbance of various lipid component levels and serious destruction of membrane structure, ultimately leading to the death of the parasites. In this review, the specific lipid metabolism pathways, correlative enzymes, and inhibitors of lipid metabolism of T. gondii are elaborated in detail to generate novel ideas for the development of anti-T. gondii drugs that target the parasites' lipid metabolism.
Epoxy composites filled with both graphene oxide (GO) and diglycidyl ether of bisphenol-A functionalized GO (DGEBA–f–GO) sheets were prepared at different filler loading levels. The correlations ...between surface modification, morphology, dispersion/exfoliation and interfacial interaction of sheets and the corresponding mechanical and thermal properties of the composites were systematically investigated. The surface functionalization of DGEBA layer was found to effectively improve the compatibility and dispersion of GO sheets in epoxy matrix. The tensile test indicated that the DGEBA–f–GO/epoxy composites showed higher tensile modulus and strength than either the neat epoxy or the GO/epoxy composites. For epoxy composite with 0.25wt% DGEBA–f–GO, the tensile modulus and strength increased from 3.15±0.11 to 3.56±0.08GPa (∼13%) and 52.98±5.82 to 92.94±5.03MPa (∼75%), respectively, compared to the neat epoxy resin. Furthermore, enhanced quasi-static fracture toughness (KIC) was measured in case of the surface functionalization. The GO and DGEBA–f–GO at 0.25wt% loading produced ∼26% and ∼41% improvements in KIC values of epoxy composites, respectively. Fracture surface analysis revealed improved interfacial interaction between DGEBA–f–GO and matrix. Moreover, increased glass transition temperature and thermal stability of the DGEBA–f–GO/epoxy composites were also observed in the dynamic mechanical properties and thermo-gravimetric analysis compared to those of the GO/epoxy composites.
The granulosa cells (GCs) of birds are essential for the reproduction and maintenance of populations in nature. Atrazine (ATR) is a potent endocrine disruptor that can interfere with reproductive ...function in females and Diaminochlorotriazine (DACT) is the primary metabolite of ATR in the organism. Melatonin (MT) is an endogenous hormone with antioxidant properties that plays a crucial role in development of animal germ cells. However, how ATR causes mitochondrial dysfunction, abnormal secretion of steroid hormones, and whether MT prevents ATR-induced female reproductive toxicity remains unclear. Thus, the purpose of this study is to investigate the protective effect of MT against ATR-induced female reproduction. In the present study, the GCs of quail were divided into 6 groups, as follows: C (Serum-free medium), MT (10 µM MT), A250 (250 µM ATR), MA250 (10 µM MT+250 µM ATR), D200 (200 µM DACT) and MD200 (10 µM MT+200 µM DACT), and were cultured for 24 h. The results revealed that ATR prevented GCs proliferation and decreased cell differentiation. ATR caused oxidative damage and mitochondrial dysfunction, leading to disruption of steroid synthesis, which posed a severe risk to GC's function. However, MT supplements reversed these changes. Mechanistically, our study exhibited that the ROS/SIRT1/STAR axis as a target for MT to ameliorate ATR-induced mitochondrial dysfunction and steroid disorders in GCs, which provides new insights into the role of MT in ATR-induced reproductive capacity and species conservation in birds.
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