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White adipose tissue wasting plays a critical role in the development and progression of cancer cachexia. However, the mechanism behind the loss of adipose tissue remains ill-defined. In this study, we found that cancer cell-derived exosomes highly expressed miR-425-3p. Administration of cancer cell-derived exosomes significantly inhibited proliferation and differentiation of human preadipocytes-viscereal (HPA-v) cells. In mature adipocytes, cancer cell-derived exosomes activated cAMP/PKA signalling and lipophagy, leading to adipocyte lipolysis and browning of white adipocytes. These exosomes-induced alterations were almost abolished by endocytosis inhibitor cytochalasin D (CytoD) and antagomiR-425-3p, or reproduced by miR-425-3p mimics. In addition, bioinformatics analysis and luciferase reporter assay revealed that miR-425-3p directly targeted proliferation-related genes such as GATA2, IGFBP4, MMP15, differentiation-related gene CEBPA, and phosphodiesterase 4B gene (PDE4B). Depletion of PDE4B enhanced cAMP/PKA signalling and lipophagy, but had no effects on HPA-v proliferation and differentiation. Taken together, these results suggested that cancer cell-derived exosomal miR-425-3p inhibited preadipocyte proliferation and differentiation, increased adipocyte lipolysis, and promoted browning of white adipocytes, all of which might contribute to adipocyte atrophy and ultimately the loss of adipose tissue in cancer cachexia. Abbreviations: ADPN: adiponectin; aP2: adipocyte protein 2 or fatty acid binding protein 4 (FABP4); BCA: bicinchoninic acid assay; BFA: bafilomycin A1; BMI: body mass index; C/EBP: CCAAT/enhancer binding protein; CEBPA: CCAAT/enhancer-binding protein-alpha; C-Exo: cancer cell-derived exosomes; CNTL: control; CREB: cAMP-response element binding protein; CytoD: cytochalasin D; ECL: chemiluminescence; GATA2: GATA Binding Protein 2; HFD: high fat diet; HSL: hormone-sensitive lipase; IGFBP4: insulin like growth factor binding protein 4; IRS-1: insulin receptor substrate-1; ISO: isoproterenol hydrochloride; KD: knockdown; KO: knock out; LC3: microtubule-associated protein 1A/1B-light chain 3; LMF: lipid mobilizing factor; LPL: lipoprotein lipase; MMP15: matrix metallopeptidase 15; Mir-Inh-C-Exo: cancer cell-derived exosomes with miR-425-3p inhibition; mTOR: mammalian target of rapamycin; Mut: mutant; N-Exo: normal cell-derived exosomes; NSCLC: non-small cell lung cancer; PBS, phosphate buffered saline; PGC-1: peroxisome proliferator-activated receptor-gamma coactivator-1; PDEs: phosphodiesterases; PKI: PKA inhibitor; PKA: cAMP-dependent protein kinase; PLIN1: Perilipin 1; PTHRP: parathyroid hormone-related protein; PVDF: polyvinylidene difluoride; shRNA: short hairpin RNA; UCP1: uncoupling protein 1; WT: wild type.

This paper presents a cost-benefit model for joint operation(JO) of wind power, photovoltaic(PV) power, thermal power and pumped storage based on economic and environmental benefits. The model is based on comprehensive consideration of the construction cost, the operating cost, the start-stop cost of the unit, the rate of wind and PV power curtailments. With the power curtailments of wind and PV being fully utilized, the economic benefits of the JO and the environmental benefits of energy saving and emission reduction are studied. The rationality and feasibility of the model are verified based on a case study, and the sensitivity of various indexes of the cost-efficiency model are analyzed. The policy recommendations for developing pumped storage power stations are put forward.

The line loss caused by corona of transmission line is not negligible in EHV power systems. Based on this, an AC/DC power flow model which includes corona influence of AC transmission line and DC transmission line to power flow and energy loss are presented in this paper. The results of an example of 7 node AC/DC transmission system show that the corona loss values obtained by the method in this paper are close to the actual measured values, and consistent with actual conditions. At the same time, the ratio of the corona loss to the total loss of the system can be analyzed by the method in real time.

For the selection and design of Ultra/Ultra High Voltage (EHV/UHV) transmission lines, the calculation of corona losses is very important content of the research. A numerical calculation method of corona losses of EHV/UHV alternating current (AC) transmission lines based on streamer theory is proposed in this paper. In this method, Peek’s formula is not used to calculate the corona onset electric field. Instead, the corona onset electric field is calculated from the physical process of corona production on the surface of the line, and the influence of raindrops on the corona onset electric field is considered according to the law of deformation of raindrops in the electric field. After the corona onset electric field was obtained, corona losses of the wire can be obtained by calculating the ion flow field of the bundled conductors. The result of the example shows that the calculation result of this method is accurate relatively compared with the measured values. The calculation method of this paper has certain practical application value for the calculation and study of EHV/UHV AC corona loss in rainy days.