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In this investigation, we employed an oxidation–reduction method to synthesize selenium nanoparticles (SeNPs) and applied a coating of sweet corn polysaccharides (SCP) to confer stability upon the SeNPs. We characterized the SCP-coated SeNPs using dynamic light scattering, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffractometry, Ultraviolet–visible spectrum, and Fourier transform infrared spectroscopy. Our findings revealed that the resulting SCP-coated SeNPs possessed an average particle size of 127.82 nm and exhibited superior inhibitory effects on α-amylase and α-glucosidase when compared to SCP in vitro experiments. The inhibition kinetics and fluorescence quenching mechanism demonstrated that the inhibitory action of SCP-coated SeNPs on both enzymes was of a competitive nature, predominantly mediated by hydrophobic interactions and hydrogen bonding. In in vivo experiments, SCP-coated SeNPs demonstrated promising hypoglycemic, hypolipidemic, and antioxidant properties in type 2 diabetes (T2DM) mice. Collectively, our study underscores the remarkable potential of SCP-coated SeNPs in ameliorating T2DM.

In this study, we aimed to investigate the impact of various ultrasound durations on the structure and bioactivity of sweet corncob polysaccharides treated with ultrasound-assisted degradation using hydrogen peroxide and ascorbic acid (H2O2–Vc). We subjected sweet corncob polysaccharides to ultrasound treatment for 0, 30, 60, and 90 min alongside the H2O2–Vc method. We then analyzed their chemical composition and structure. Additionally, we administered these polysaccharides to mice with type 2 diabetes (T2DM) through gavage at a dosage of 200 mg/kg/day. The results indicated a significant reduction in the molecular weight of the degraded sweet corncob polysaccharides, while their composition remained relatively stable. However, the basic structure of the polysaccharides was retained. In vivo experiments demonstrated that ultrasound-assisted degradation of these polysaccharides had a positive impact on T2DM, particularly the 60-minute ultrasound treatment (UH-DSCBP-60 min), which effectively controlled blood glucose levels by regulating glycolipid metabolism in the livers of mice with T2DM. This approach also reduced inflammation and oxidative stress levels and inhibited disaccharide activity in the small intestine. We demonstrated that ultrasound can positively affect the sweet corncob polysaccharides hypoglycemic activity. The findings of our study provide a theoretical foundation for the valuable utilization of sweet corncob polysaccharides.

This study aimed to enhance the utilization value of sweet corn cob, an agricultural cereal byproduct. Sweet corn cob polysaccharide-ron (III) complexes were prepared at four different temperatures (40 °C, 50 °C, 60 °C, and 70 °C). It was demonstrated that the complexes prepared at different temperatures were successfully bound to iron (III), and there was no significant difference in chemical composition; and SCCP-Fe-C demonstrated the highest iron content. The structural characterization suggested that sweet corn cob polysaccharide (SCCP) formed stable β-FeOOH iron nuclei with −OH and −OOH. All the four complexes’ thermal stability was enhanced, especially in SCCP-Fe-C. In vitro iron (III) release experiments revealed that all four complexes were rapidly released and acted as iron (III) supplements. Moreover, in vitro antioxidant, α-glucosidase, and α-amylase inhibition studies revealed that the biological activities of all four complexes were enhanced compared with those of SCCP. SCCP-Fe-B and SCCP-Fe-C exhibited the highest in vitro antioxidant, α-glucosidase, and α-amylase inhibition abilities. This study will suggest using sweet corn cobs, a natural agricultural cereal byproduct, in functional foods. Furthermore, we proposed that the complexes prepared from agricultural byproducts can be used as a potential iron supplement.

BackgroundHER2-positive breast cancer was aggressive, resulting in a poorer prognosis. This multicenter study analyzed the real-world data of women treated with pyrotinib-based therapy, aiming to describe their characteristics, treatment regimens, and to investigate the clinical outcomes.MethodsA total of 141 patients with HER2-positive breast cancer were enrolled from February 2019 to April 2020. Last follow-up time was February 2021. All patients were treated with pyrotinib-based therapy in 21-day cycles. The primary endpoint was progression-free survival (PFS).ResultsThe median PFS (mPFS) for pyrotinib-based therapy was 12.0 months (95%CI 8.1-17.8) in all patients. Among the patients with liver metastases, mPFS was 8.7 months (95%CI, 6.3-15.4) compared to 12.3 months (95%CI, 8.8-23.3) for patients without liver metastases (P=0.172). In addition, patients receiving pyrotinib-based therapy as their >2 lines treatment had a numerically lower mPFS than those receiving pyrotinib-based therapy as their ≤2 lines treatment [8.4 (95%CI, 5.9-15.4) vs. 15.1 (95%CI, 9.3-22.9) months, P=0.107]. The mPFS was 12.2 months (95%CI, 7.9-18.8) in patients with previous exposure to trastuzumab and 11.8 months (95%CI, 6.8-22.9) in patients without previous exposure to trastuzumab (P=0.732). Moreover, mPFS in patients receiving regimens with and without capecitabine were 15.1 months (95%CI, 10.0-18.8) and 8.4 months (95%CI, 6.7-22.9), respectively (P=0.070). Furthermore, in patients with brain metastases, estimated 6-month PFS rate was 70.0%, and rate at 12 months was 60.0%. Seventy patients with measurable lesions were evaluable for response. The objective response rate was 38.6% and disease control rate was 85.7%. The most common adverse event was diarrhea (85.0%).ConclusionPyrotinib-based therapy showed promising efficacy in patients with HER2-positive breast cancer and was well tolerated, especially in patients treated with pyrotinib as ≤2 lines treatment and receiving regimens with capecitabine. The results of this real-world study further confirmed the intriguing efficacy of pyrotinib.

Multi-terminal high voltage direct current (MTDC) has many features including multiple sending ends, multiple receiving ends, and high transmission capacity. These make it highly competitive in both technical and economic terms. In designing a MTDC system, the calculation of the main circuit steady-state parameter plays a fundamental role. However, existing researches mainly focus on parallel multi-terminal DC transmission systems (P-MTDC), few looks into series multi-terminal DC transmission systems (S-MTDC). Therefore, this study researches into the calculation of the main circuit steady-state parameters for S-MTDC transmission systems. First of all, the two types of MTDC transmission systems, S-MTDC and P-MTDC, are briefly introduced and compared. Then, the calculation of the steady-state parameter of the main circuit for two-terminal high voltage direct current (HVDC) transmission systems is explained. Based on this calculation method, research on the main circuit steady-state parameter for S-MTDC transmission systems is conducted and the design of calculation of steady-state parameter of the main circuit is presented in detail. Finally, this study designs a series four-terminal HVDC systems and verifies the calculation method of the steady-state parameter of the main circuit.

Resonance or harmonic amplification occurs when the frequency of the harmonics generated by the converter station is near the inherent resonance frequency of the substation. Considering there are six DC projects in the Yunnan power grid, analysing the resonant characteristics of the grid is imperative for safety reasons. This study establishes a simulation platform of the Yunnan power grid based on the Power System Analysis Software Package and formulates the modelling principles and simulation steps. In order to successfully analyse the resonant characteristics of a substation under normal operation mode and put forward any necessary suggestions, the impedance frequency of all 500 kV substations in the power grid are scanned. This is followed by studying, the influence of different operation modes of Yunnan power grid and different operation modes of DC system of Luxi converter station on the resonant characteristics of Yunnan substation. Based on these results, effective measures for resonance suppression are proposed. [ABSTRACT FROM AUTHOR]

Yongfu high voltage direct current (HVDC) project in Yunnan is the main access to send the power out and also an important part of the channel of transmission of power in west to east in China southern power grid. However, the Funing Converter Station of the project connects to a weak AC system; thus, there is a need for a Static Synchronous Compensator (STATCOM) to compensate the reactive power. This study presents the principle of the STATCOM, all kinds of the topologies of STATCOM, with their advantages and disadvantages compared to each other and the representative projects. Then, the cascade STATCOM is emphatically analysed that is applied to the project. Also, the cascade STATCOM model and the project model are established in PSCAD/EMTDC. Afterwards, the effect of STATCOM on the converter station is studied, which works in steady state and in transient of varieties of short circuit faults. Finally, the simulation results verify the effectiveness of cascade STATCOM on stabilising the voltage. [ABSTRACT FROM AUTHOR]

In this work, ethylene-propylene-ethylene (EPE) oxide triblock copolymers were found to be effective suppressors for microvia filling during copper electroplating. The studied EPE copolymers were divided into two groups according to their solubility and compositions. The first group was composed of EPE I000, EPE 2000, and EPE 3500, and the second group contained EPE 2450, EPE 2900, and EPE 8000. In particular, the function of the triblock copolymer suppressors (e.g. EPE 2900) and their synergistic effect with other additives during copper electroplating were studied by galvanostatic measurements, suggesting that the suppression strength was greatly dependent on Cl-. In addition, cyclic voltammetry (CV) measurements indicated that a given suppressor in the plating bath required an optimal Cl- concentration to realize the strongest suppression strength. Then the filling performance of the plating bath using different suppressors was systematically compared by galvanostatic measurements and filling plating experiments in the plating bath with a fixed Cl- concentration (60 ppm), an optimal CI- concentration, and a wide operation window of Cl respectively. These experimental analyzes indicated that EPE 2000 and EPE 2900 were the best suppressors in the first and second group, respectively. The relevant mechanism of triblock copolymer suppressors for microvia filling was discussed. [ABSTRACT FROM AUTHOR]