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Thermoplastic polyamide elastomers (TPAEs) were synthesized using polyamide 6 (PA6) as hard segments and polyethylene glycol (PEG) as soft segments. The prepared TPAEs showed a superior mechanical property and thermal property, which the strength and elongation-at-break reached 35.50 [+ or -] 3.54 MPa and (316.05 [+ or -] 20.58)%, respectively, when the molecular weight of soft segment was 600. Furthermore, crystallization property and microphase separation of TPAEs were also investigated in detail, having a significant influence on the foaming behavior of the obtain elastomers. Owing to the restriction of crystalline hard segments, only a few cells formed in the amorphous soft segment regions at foaming temperature of 140[degrees]C, while it transformed to larger cells with a thin cell wall at foaming temperature of 160[degrees]C and above. When the molecular weight of soft segment increased from 300 to 1000, the average cell size of the foamed TPAEs at 160[degrees]C enlarged from 28.73 to 42.17 [micro]m, while the cell density decreased from 5.26 x [10.sup.8] #/[cm.sup.3] to 4.25 x [10.sup.8] #/[cm.sup.3], both expansion ratio and shrinkage ratio increased gradually. KEYWORDS crystallization, foaming behavior, mechanical property, microphase separation, thermoplastic polyamide elastomers, 1 | INTRODUCTION Thermoplastic polyamide elastomers (TPAEs) are a new member of the thermoplastic elastomer family, composed of rubber-phase polyester or polyether and plastic-phase polyamide (PA), including PA6, PA12, PA11, [...]

It is known that the abnormal expression of specific cellular miRNAs is closely related to cell apoptosis, and so monitoring the level change of these miRNAs can in principle be used to evaluate the process of apoptosis stimulated by drugs. Towards this goal, here we construct an ultrasensitive electrochemiluminescence (ECL) nanoplatform via the target miRNA-triggered immobilization of spherical nucleic acid enzymes (SNAzymes) onto tetrahedral DNA nanostructures on the electrode surface, which catalyzes the luminol–H2O2 reaction to output an ECL signal. This enables the sensitive and specific detection of two apoptosis-related miRNAs, miR-21 and miR-133a, with a detection limit of 33 aM. Furthermore, we employed the developed ECL nanoplatform to monitor the levels of these two miRNAs inside cancer cells stimulated by DOX, showing that the level of miR-21 decreases, while that of miR-133a increases in the early apoptotic cells. This difference highlights the distinct roles of the two target miRNAs, where miR-21 promotes the early apoptosis of cancer cells, whereas miR-133a suppresses it, providing new insight into cell physiological processes. [ABSTRACT FROM AUTHOR]

With the development of the economy and society, the importance of a secure and stable electricity supply continues to increase. However, the power grid is facing the test of excess installed capacity, the waste of renewable energy, and a low comprehensive utilization rate. This problem stems from the inconsistent peak–valley differences between power production and consumption, and the lack of clear electricity price signals, which disrupts the safe and stable operation of the power market. This paper combines the interactive transactions among clean energy power generation companies, users, and energy storage, explores how the system optimization model can be reflected in the power market through regulatory measures, and formulates the optimal output scheme of the system under the constraints of clean energy power generation forecast data, user base load forecast data, demand-side resource regulation ability, and energy storage system regulation ability to achieve the goals of comprehensive clean energy power consumption and minimum cost for users. A comprehensive analysis of the proposed model was conducted using actual data from a certain province in China, the results show that the consumption of clean energy will increase by 3% to full consumption and the total cost of users will be 32% lower than that of time-of-use (TOU) power prices, which proves the potential of the proposed joint optimization model in absorbing clean energy and the effectiveness of the market mechanism. [ABSTRACT FROM AUTHOR]