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Copper (Cu) is vital for macroalgae's functions, but high concentrations can be toxic. Rising CO 2 levels affect algal growth and Cu bioavailability. In this study, the results reveal that at 5 °C, low Cu increased Ulva linza growth, while high Cu and elevated CO 2 decreased growth. At 10 °C, low Cu and elevated CO 2 enhanced growth, but high Cu did not have a significant impact. At 15 °C, high Cu reduced growth, but elevated CO 2 offset this effect. Furthermore, under elevated CO 2 conditions, the chloroplast structure of the algae appeared to be denser, accompanied by a large amount of starch granules, compared to low CO 2 conditions. These results emphasize that lower temperatures, in conjunction with elevated CO 2 concentration, could intensify the toxic effects of high Cu concentrations on thalli. However, at higher temperatures, elevated CO 2 concentration appeared to be capable of mitigating the detrimental effects of heavy metals on algae., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Current sprayable hydrogel masks lack the stepwise protection, cleansing, and nourishment of extensive wounds, leading to delayed healing with scarring. Here, we develop a sprayable biomimetic double wound mask (BDM) with rapid autophasing and hierarchical programming for scarless wound healing. The BDMs comprise hydrophobic poly (lactide- co -propylene glycol- co -lactide) dimethacrylate (PLD) as top layer and hydrophilic gelatin methacrylate (GelMA) hydrogel as bottom layer, enabling swift autophasing into bilayered structure. After photocrosslinking, BDMs rapidly solidify with strong interfacial bonding, robust tissue adhesion, and excellent joint adaptiveness. Upon implementation, the bottom GelMA layer could immediately release calcium ion for rapid hemostasis, while the top PLD layer could maintain a moist, breathable, and sterile environment. These traits synergistically suppress the inflammatory tumor necrosis factor-α pathway while coordinating the cyclic guanosine monophosphate/protein kinase G-Wnt/calcium ion signaling pathways to nourish angiogenesis. Collectively, our BDMs with self-regulated construction of bilayered structure could hierarchically program the healing progression with transformative potential for scarless wound healing.

In single-photon emission computed tomography (SPECT), a micro-sized 99m Tc source is routinely used for performance measurement, geometry calibration, and system matrix generation. Therefore, a micro-sized source is critical in nuclear instrument production and quality control. Standard methods can only produce a point source with a large size and low total activity, as they are limited by the concentration of the 99m Tc solution. The absorption of 99m Tc on ion exchange resins has been used; however, few studies have quantitatively evaluated the absorption process and optimized the source activity. This paper proposes a procedure for producing a micro-sized 99m Tc resin source with a super-high concentration, as well as a method for the fast measurement of the point source time-activity curve (TAC). Experiments on two resin point sources with diameters of 0.681 mm and 0.326 mm were carried out. Two semi-empirical models, including the first kinetic model and the pseudo-second-order rate equation model, were used to fit TACs. The results show the first kinetic model fit better, which suggests an acquisition time of 2-4 h is needed for optimization. The verification experiment demonstrates a resin point source with a diameter of 0.35 mm and total activity of 10.6 mCi (i.e., 59.1 Ci/mL concentration) was produced., (Copyright © 2022 Elsevier Ltd. All rights reserved.)