3 research outputs found
Optimal real-time power dispatch of power grid with wind energy forecasting under extreme weather
With breakthroughs in the power electronics industry, the stability and rapid power regulation of wind power generation have been improved. Its power generation technology is becoming more and more mature. However, there are still weaknesses in the operation and control of power systems under the influence of extreme weather events, especially in real-time power dispatch. To optimally distribute the power of the regulation resources in a more stable manner, a wind energy forecasting-based power dispatch model with time-control intervals optimization is proposed. In this model, the outage of the wind energy under extreme weather is analyzed by an autoregressive integrated moving average model (ARIMA). Additionally, the other regulation resources are used to balance the corresponding wind power drop and power mismatch. Meanwhile, an algorithm names weighted mean of vectors (INFO) is employed to solve the real-time power dispatch and minimize the power deviation between the power command and real output. Lastly, the performance of the proposed optimal real-time power dispatch is executed in a simulation model with ten regulation resources. The simulation tests show that the combination of ARIMA and INFO can effectively improve the power control performance of the PD-WEF system
Biochemistry and Molecular Biology Aberrant Buildup of All-Trans-Retinal Dimer, a Nonpyridinium Bisretinoid Lipofuscin Fluorophore, Contributes to the Degeneration of the Retinal Pigment Epithelium
PURPOSE. Nondegradable fluorophores that accumulate as deleterious lipofuscin of RPE are involved in pathological mechanisms leading to the degeneration of RPE in AMD. A2E, a major component of RPE lipofuscin, could cause damage to RPE cells. Nevertheless, all-trans-retinal dimer (atRAL dimer) was found to be much more abundant than that of A2E in eyes of Abca4 À/À Rdh8 À/À double-knockout (DKO) mice, a rodent model showing the typical characteristics of retinopathies in AMD patients. Our aim was to elucidate the effect and mechanism of atRAL dimer-induced RPE degeneration. METHODS. Eyes harvested from C57BL/6J wild-type (WT) and Abca4 À/À Rdh8 À/À DKO mice were examined by HPLC. Cellular uptake, subcellular localization, 5-bromo-2-deoxyuridine (BrdU), Cdc25C, DNA strand breaks, mitochondrial membrane potential (DWm), and cytochrome c were analyzed by fluorescence microscopy. Cellular toxicity was assayed by lactate dehydrogenase (LDH) assay and dead cell staining. Apoptosis and cell-cycle stages were detected by flow cytometry. Furthermore, in vitro and in vivo expression of proteins associated with cell cycle and apoptosis was measured by immunoblot assays. RESULTS. All-trans-retinal dimer clearly could damage RPE cell membrane and inhibit the proliferation of RPE cells as well as induce DNA damage and cell-cycle arrest at the G2/M phase via activating the ATM/ATR-Chk2-p53 signaling pathway. Moreover, this di-retinal adduct triggered mitochondrion-associated apoptosis in RPE cells. Evidence from the cellbased experiments was also corroborated by a remarkable abnormality in expression of proteins associated with cell cycle (Cyclin B1 and Cdc2) and apoptosis (p53, Bcl-2 and Bax) in the RPE of Abca4 CONCLUSIONS. These findings suggest that atRAL dimer that accumulates beyond a critical level, facilitates age-dependent RPE degeneration. Keywords: all-trans-retinal dimer, bisretinoid lipofuscin, retinal pigment epithelium, cell cycle, proliferation inhibition, mitochondrial dysfunction A ge-related macular degeneration (AMD) is a retinal degenerative disease that is a major cause of irreversible vision loss in individuals older than 50 years in many developed countries, especially in the United States. 5 High levels of RPE lipofuscin have been considered to be associated with degeneration of the RPE 6,7 and concomitant disturbance in the daily phagocytosis of shed photoreceptor outer segments by RPE cells, a critical process for the maintenance of the retina. 8 Although excess deposition of lipofuscin pigment granules in the RPE contributes to increased morbidity of AMD, the mechanism underlying RPE lipofuscin-induced retinal degeneration is not fully understood as yet. An inadvertent consequence of retinal metabolism necessary for regeneration of visual chromophore 11-cis-retinal is the formation of retinal-derived compounds that undergo synthesis in photoreceptor outer segments of neural retina and are secondarily deposited in the RPE as predominant hydrophobic components of toxic lipofuscin. 9,10 Several lipofuscin fluorophores have been structurally identified in vertebrate RPE, including A2
Modulation of Dendritic Cell Function via Nanoparticle-Induced Cytosolic Calcium Changes
Calcium nanoparticles have been investigated for applications,
such as drug and gene delivery. Additionally, Ca2+ serves
as a crucial second messenger in the activation of immune cells. However,
few studies have systematically studied the effects of calcium nanoparticles
on the calcium levels and functions within immune cells. In this study,
we explore the potential of calcium nanoparticles as a vehicle to
deliver calcium into the cytosol of dendritic cells (DCs) and influence
their functions. We synthesized calcium hydroxide nanoparticles, coated
them with a layer of silica to prevent rapid degradation, and further
conjugated them with anti-CD205 antibodies to achieve targeted delivery
to DCs. Our results indicate that these nanoparticles can efficiently
enter DCs and release calcium ions in a controlled manner. This elevation
in cytosolic calcium activates both the NFAT and NF-κB pathways,
in turn promoting the expression of costimulatory molecules, antigen-presenting
molecules, and pro-inflammatory cytokines. In mouse tumor models,
the calcium nanoparticles enhanced the antitumor immune response and
augmented the efficacy of both radiotherapy and chemotherapy without
introducing additional toxicity. Our study introduces a safe nanoparticle
immunomodulator with potential widespread applications in cancer therapy