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This paper proposes a modeling and analysis method for a Caputo–Fabrizio (C-F) definition-based fractional-order Boost converter with fractional-order inductive loads. The proposed method analyzes the system characteristics of a fractional-order circuit with three state variables. Firstly, this paper constructs a large signal model of a fractional-order Boost converter by taking advantage of the state space averaging method, providing accurate analytical solutions for the quiescent operating point and the ripple parameters of the circuit with three state variables. Secondly, this paper constructs a small signal model of the C-F definition-based fractional-order Boost converter by small signal linearization, providing the transfer function of the fractional-order system with three state variables. Finally, this paper conducts circuit-oriented simulation experiments where the steady-state parameters and the transfer function of the circuit are obtained, and then the effect of the order of capacitor, induced inductor, and load inductor on the quiescent operating point and ripple parameters is analyzed. The experimental results show that the simulation results are consistent with those obtained by the proposed mathematical model and that the three fractional orders in the fractional model with three state variables have a significant impact on the DC component and steady-state characteristics of the fractional-order Boost converter. In conclusion, the proposed mathematical model can more comprehensively analyze the system characteristics of the C-F definition-based fractional-order Boost converter with fractional-order inductive loads, benefiting the circuit design of Boost converters. [ABSTRACT FROM AUTHOR]

This paper presents a novel approach for modeling Boost converters using the Caputo–Fabrizio (C-F) definition-based fractional-order model to address singular characteristics in fractional-order definitions and enhance model accuracy. A small signal modeling method is proposed to improve the accuracy of circuit parameter design and to derive state-averaged models, state-space equations, and transfer functions. The influence of capacitor and inductor orders on steady-state characteristics is analyzed and the influence of fractional-order on ripple characteristics is investigated through simulation. When the fractional-order approaches 1, the output voltage increases and the inductance current decreases, with waveform jitter mitigation. Moreover, boundary conditions for continuous conduction mode operation are established based on ripple characteristics. The numerical and circuit-oriented simulations verify the correctness of the proposed model. Finally, the orders and accurate parameters of capacitors and inductors based on the C-F definition are determined and the experiments are conducted. The comparison between the experimental and simulation results demonstrates that the proposed model can accurately describe the steady-state characteristics of the practical circuit systems, which further validates the accuracy of the proposed method. [ABSTRACT FROM AUTHOR]

The Caputo–Fabrizio (C–F) definition, which solves the singularity problem in the Caputo definition, has been preliminarily applied in the field of circuit system modeling. However, the complex characteristics of the C–F definition-based circuit systems are still understudied. Therefore, this paper proposes a C–F definition-based fractional-order RLC (CF-FORLC) circuit model and analyzes its basic characteristics. First, the effects of different component orders on the performance parameters including the impedance, quality factor, and bandwidth are analyzed, which gives insights into the design of CF-FORLC. Then, the analytical solutions and the frequency-domain characteristics of CF-FORLC with different capacitance and inductance orders under arbitrary input are derived. Finally, the data of actual circuits are fitted to obtain the parameters of the CF-FORLC model, and the orders of the C–F definition-based capacitors and inductors are estimated. The results of the comparative experiments show that the proposed modeling scheme can improve the consistency of the dynamic performance of the model with that of the actual circuit. In addition, the proposed CF-FORLC model shows higher accuracy and flexibility with more adjustable parameters. [ABSTRACT FROM AUTHOR]

International cooperation for renewable energy under the Belt and Road Initiative (BRI) plays a pivotal role in the transition to low-carbon energy in BRI developing countries. However, the rise in energy, debt, food, and geopolitical crises, along with the unique internal challenges found in different BRI developing countries, introduce multiple uncertainties to international renewable energy cooperation (IREC). Therefore, it is crucial to analyze the risks associated with IREC across different BRI countries by incorporating international cooperation theory. This study proposes an analytical framework comprising cooperation consensus–state capacity–institutional environment, which encompasses the willingness to cooperate, national capabilities, and international institutional considerations. An evaluation indicator system is constructed based on this framework. The study optimizes the indicator weights obtained from expert surveys using the analytic hierarchy process and the criteria importance through intercriteria correlation method. A quantitative assessment of IREC risks was conducted for 114 BRI countries from 2010 to 2020. The results indicate a gradual reduction in IREC risks between China and BRI countries. Regional risk assessments reveal that Southeast Asia exhibits the lowest average risk, while Africa not only records the highest average risk but also indicates substantial cooperation potential. Therefore, we recommend a comprehensive approach to risk mitigation. Such an approach would include gradually improving cooperation mechanisms, promoting both top-down and bottom-up cooperation, encouraging the involvement of multiple stakeholders, and prioritizing early-stage risk assessments and research. • A new analytical framework based on international cooperation theories. • A dynamic risk map for Belt and Road renewable energy cooperation. • The combination of AHP and CRITIC. • Tailored risk mitigation strategies for different regions. [ABSTRACT FROM AUTHOR]

Many electrical systems can be characterized more authentically by fractional-order dynamic systems. The Atangana–Baleanu and the Caputo–Fabrizio fractional derivatives have solved the singularity problem in Caputo derivative. This work uses Atangana–Baleanu and Caputo–Fabrizio fractional derivatives to model the fractional-order mutual inductance in the frequency domain. To use the fractional mutual inductance in circuit design, the T-model equivalent circuits are presented with different fractional derivatives. The fractional impedance matching networks based on proposed fractional mutual coupling circuits are simulated as an application. The impedance characteristics of networks with different fractional orders are analyzed. The results indicate that the proposed fractional mutual coupling circuits based on Atangana–Baleanu and Caputo–Fabrizio fractional derivatives can be applied to the complex electrical systems to increase the design degree of freedom, which provides more choices for describing the nonlinear characteristics of the system. [ABSTRACT FROM AUTHOR]

Pathological neovascularization is a pivotal biological process in wet age-related macular degeneration (AMD), retinopathy of prematurity (ROP) and proliferative diabetic retinopathy (PDR), in which macrophages (Mφs) play a key role. Tip cell specialization is critical in angiogenesis; however, its interconnection with the surrounding immune environment remains unclear. Succinate is an intermediate in the tricarboxylic acid (TCA) cycle and was significantly elevated in patients with wet AMD by metabolomics. Advanced experiments revealed that SUCNR1 expression in Mφ and M2 polarization was detected in abnormal vessels of choroidal neovascularization (CNV) and oxygen-induced retinopathy (OIR) models. Succinate-induced M2 polarization via SUCNR1, which facilitated vascular endothelial cell (EC) migration, invasion, and tubulation, thus promoting angiogenesis in pathological neovascularization. Furthermore, evidence indicated that succinate triggered the release of RBP4 from Mφs into the surroundings to regulate endothelial sprouting and pathological angiogenesis via VEGFR2, a marker of tip cell formation. In conclusion, our results suggest that succinate represents a novel class of vasculature-inducing factors that modulate Mφ polarization and the RBP4/VEGFR2 pathway to induce pathological angiogenic signaling through tip cell specialization. [ABSTRACT FROM AUTHOR]

To investigate the tolerability and safety of two sublingual tree pollen extracts approved in 2018, a non-interventional study (NIS) was performed. This NIS was an 8-month observational study conducted at 84 sites throughout Germany. Study participants received either a sublingual liquid allergen extract of birch pollen (SBPE) or a liquid allergen extract consisting of a mixture of birch, hazel, and alder tree pollen (STPE). Data from 432 patients were analyzed for the occurrence of adverse events and patient compliance. At least one local reaction occurred in 69 (22.2%) patients, whereas systemic reactions were only observed in 27 (6.3%) patients. STPE-treated patients developed systemic reactions more frequently than SBPE-treated patients (SBPE: 9 (4.3%) vs. STPE: 18 (8.0%)). Only one patient developed a systemic grade III reaction. Severe systemic grade IV reactions were not observed. A total of 348 (98.6%) of the patients who completed all visits were satisfied or very satisfied with the sublingual immunotherapy (SLIT), and 322 (71%) patients completed all visits. Both investigated products were well tolerated by the patients and demonstrated a good safety profile. AEs were observed less frequently than in the preceding clinical phase III trial, and no new safety concerns were identified. [ABSTRACT FROM AUTHOR]

Bacterial endophthalmitis (BE) is an acute eye infection and potentially irreversible blinding ocular disease. The empirical intravitreous injection of antibiotic is the primary treatment once diagnosed as BE. However, the overuse of antibiotic contributes to the drug resistance of pathogens and the retinal toxicity of antibiotic limits its application in clinic. Herein, a cationic aggregation‐induced emission luminogens named with triphenylamine thiophen pyridinium (TTPy) is reported for photodynamic treatment of BE. TTPy can selectively discriminate and kill bacteria efficiently over normal ocular cells. More importantly, TTPy shows excellent antibacterial ability in BE rat models infected by Staphylococcus aureus. Meanwhile, the bacterial killing behavior triggered by TTPy induces innate immune response at an early stage of infection, limiting subsequent robust inflammation and protecting retina from bacterial toxins and inflammation‐induced bystander damage. In addition, TTPy performs better antibacterial ability than commercially used Rose Bengal, suggesting its excellent capability of vision salvage in acute BE. This study exhibits an efficient photodynamic antibacterial treatment to BE, which induces an early intraocular immune response and saves useful vision, endowing TTPy a promising potential for clinical application of ocular infections. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration (AMD) is a multifactor disease, which is primarily characterized by retinal pigment epithelium (RPE) cell loss. Since the retina is the most metabolically active tissue, RPE cells are exposed to consistent oxidative environment. So, oxidation-induced RPE cell death has long been considered a contributor to the onset of AMD. Here, we applied a retinal degeneration (RD) rat model induced by blue light-emitting diode (LED) and a cell model constructed by H2O2 stimulus to mimic the prooxidant environment of the retina. We detected that the expression of miR-27a was upregulated and the expression of FOXO1 was downregulated in both models. So, we furtherly investigated the role of miR-27a-FOXO1 axis in RPE in protesting against oxidants. Lentivirus-mediated RNA was injected intravitreally into rats to modulate the miR-27a-FOXO1 axis. Retinal function and histopathological changes were evaluated by electroretinography (ERG) analysis and hematoxylin and eosin (H&E) staining, respectively. Massive photoreceptor and RPE cell death were examined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The damage to the retina was aggravated in the FOXO1 gene-knockdown and miR-27a-overexpression groups after exposure to LED but was alleviated in the FOXO1 gene-overexpression or miR-27a-knockdown groups. Dual luciferase assay was used to detect the binding site of miR-27a and FOXO1. Upregulated miR-27a inhibited the expression of FOXO1 by directly binding to the FOXO1 mRNA 3 ′ UTR and decreased the autophagy activity of ARPE-19 cells, resulting in the accumulation of reactive oxygen species (ROS) and decrease of cell viability. The results suggest that miR-27a is a negative regulator of FOXO1. Also, our data emphasize the prominent role of miR-27a/FOXO1 axis in modulating ROS accumulation and cell death in RPE cell model under oxidative stress and influencing the retinal function in the LED-induced RD rat model. [ABSTRACT FROM AUTHOR]

This study employs the Caputo–Fabrizio and Atangana–Baleanu fractional derivatives to determine the impedance and admittance model of fractional capacitor and inductor. The analog implementation circuits are proposed aiming at fractional-order electric elements based on these two derivatives, which can be widely used in a variety of electrical systems using new fractional operators. Constant phase capacitor and inductor are approximated by the Oustaloup algorithm and the recursive net-grid-type analog circuit, respectively. Based on that, approximation circuits of fractional electric components under Caputo–Fabrizio and Atangana–Baleanu definitions are given. For the purpose of judging whether the implementation topology of fractional-order capacitor and inductor is accurate, taking fractional RC and RL circuit defined by Caputo, Caputo–Fabrizio and Atangana–Baleanu derivatives as examples, the comparison of numerical and circuit simulations is carried out. The correctness of the analog implementation circuits using the Caputo–Fabrizio and Atangana–Baleanu definitions is verified. Fractional-order RC charging circuit experiments based on Caputo, Caputo–Fabrizio and Atangana–Baleanu derivatives are taken as examples. Several experiments with different fractional-order and circuit parameters are carried out. The validity of the implementation methods is ulteriorly proved with experiment data. [ABSTRACT FROM AUTHOR]

The crucial effect of vascular endothelial growth factor (VEGF)-induced vascular angiogenesis has been well known in corneal neovascularization (CNV). This research aimed to determine the underlying value and mechanism of Meg3 on CNV in vivo and in vitro. In an alkali-burned mouse model, length and area of new vessels were increased along with thinning of corneal epithelium, accompanied by the overexpression of Meg3. Notably, subconjunctival injection of shMeg3 suppressed the degree of injury in cornea, causing expression of the angiogenesis markers--VEGF-A and CD31 decreased. In VEGF-induced human umbilical vein endothelial cells (HUVECs), knockdown of Meg3 antagonized the enhancement of viability, proliferation, wound healing ability and angiogenesis by VEGF. The proteins expression of VEGF-A, CD31, SDF-1/CXCR4 as well as phosphoraylation-Smad2/3 pathways, which were related to angiogenesis, were reduced with Meg3 deficiency. Overall, knockdown of Meg3 alleviated formation of neovascularization in alkali-burned corneas and reduced VEGF-induced angiogenesis by inhibiting SDF-1/CXCR4 and Smad2/3 signaling in vitro. • Meg3 has a time-dependent relationship with corneal neovascularization(CNV). • Knockdown of Meg3 alleviated pathological changes and angiogenic responses in CNV. • SiMeg3 reduced VEGF-induced proliferation, migration and angiogenesis in HUVEC. • SiMeg3 inhibited expression of SDF-1/CXCR4 and Smad2/3 in VEGF-induced HUVEC. [ABSTRACT FROM AUTHOR]