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Creatures, such as Venus flytrap and hummingbirds, capable of rapid predation through snap‐through transition, provide paradigms for the design of soft actuators and robots with fast actions. However, these artificial "snappers" usually need contact stimulations to trigger the flipping. Reported here is a constrained anisotropic poly(N‐isopropylacrylamide) hydrogel showing fast snapping upon light stimulation. This hydrogel is prepared by flow‐induced orientation of nanosheets (NSs) within a rectangular tube. The precursor containing gold nanoparticles is immediately exposed to UV light for photopolymerization to fix the ordered structure of NSs. Two ends of the slender gel are clamped to form a buckle with bistability nature, which snaps to the other side upon laser irradiation. Systematic experiments are conducted to investigate the influences of power intensity and irradiation angle of the laser, as well as thickness and buckle height of the gel, on the snapping behaviors. The fast snapping is further used to kick a plastic bead and control the switch state. Furthermore, synergetic or oscillated snapping of the gel with two buckles of opposite directions is realized by inclined irradiation of a laser or horizontal irradiation with two lasers, respectively. Such light‐steered snapping of hydrogels should merit designing soft robots, energy harvests, etc. [ABSTRACT FROM AUTHOR]

Converting poly(ethylene terephthalate) (PET) into metal–organic frameworks (MOFs) has emerged as a promising innovation for upcycling of waste plastics. However, previous solvothermal methods suffer from toxic solvent consumption, long reaction time, high pressure, and high temperature. Herein, a mechanochemical milling strategy was reported to transform waste PET into a series of MOFs with high yields. This strategy had the merits of solvent‐free conditions, ambient reaction temperature, short running time, and easy scale‐up for large‐scale production of MOFs. The as‐prepared MOFs exhibited definite crystal structure and porous morphology composed of agglomerated nanoparticles. It was proven that, under mechanochemical milling, PET was firstly decomposed into 1,4‐benzenedicarboxylate, which acted as linkers to coordinate with metal ions for forming fragments, followed by the gradual arrangement of fragments into MOFs. This work not only promotes high value‐added conversion of waste polyesters but also offers a new opportunity to produce MOFs in a green and scalable manner. [ABSTRACT FROM AUTHOR]

Solar evaporation is recognized as a prospective technique to produce freshwater from non‐drinkable water using inexhaustible solar energy. However, it remains a challenge to fabricate low‐cost solar evaporators with obviously reduced water evaporation enthalpy to achieve high evaporation rates. Herein, N,O dual‐doped carbon foam (NCF) is fabricated from the low‐temperature carbonization of poly(ethylene terephthalate) (PET) waste by melamine/molten salts at 340 °C. During carbonization, melamine reacts with carboxylic acids of PET degradation products to yield a crosslinking network, and then molten salts catalyze the decarboxylation and dehydration to construct a stable framework. Owing to rich N,O‐containing groups, 3D interconnected pores, super‐hydrophilicity, and ultra‐low thermal conductivity (0.0599 W m−1 K−1), NCF not only achieves high light absorbance (ca. 99%) and solar‐to‐thermal conversion, but also promotes the formation of water cluster to reduce water evaporation enthalpy by ca. 37%. Consequently, NCF exhibits a high evaporation rate (2.4 kg m−2 h−1), surpassing the‐state‐of‐the‐art solar evaporators, and presents good anti‐acid/basic abilities, long‐term salt‐resistance, and self‐cleaning ability. Importantly, a large‐scale NCF‐based outdoor solar desalination device is developed to produce freshwater. The daily freshwater production amount per unit area (6.3 kg) meets the two adults' daily water consumption. The trash‐to‐treasure strategy will give impetus to the development of low‐cost, advanced solar evaporators from waste plastics for addressing the global freshwater shortage. [ABSTRACT FROM AUTHOR]

Objective: To investigate the protective effects of valproic acid (VPA) on myocardium in rats following lethal burn injury and its mechanism., Methods: Seventy-eight Sprague-Dawley (SD) rats were randomly assigned to four groups: sham-scald group (n=10), sham-scald + VPA group (n=10), scald group (n=29), and scald + VPA group (n=29). Rats in the latter two groups were subjected to 55% total body surface area (TBSA) third-degree burns by immersing the back of the trunk for 15 seconds, both lower extremities for 15 seconds, and the abdomen for 8 seconds in 80 centigrade water. Sham-scald rats were immersed in 37 centigrade water instead. Rats were then subcutaneously injected with VPA (300 mg/kg) or normal saline as control. Blood of 5 rats in each group was with drawn from the abdominal aorta at 6 hours after injury for measurement of plasma creatine kinase-MB (CK-MB) activities; then the rats were sacrificed and heart tissues were harvested for the measurement of acetylated histone H3 and activated caspase-3 by Western Blot. The remaining rats were used for 12-hour survival analysis., Results: Compared with sham-scald group, there was a significant increase in plasma CK-MB activities (5 438.0 ± 413.6 U/L vs. 2 881.0 ± 324.8 U/L, P<0.05) and activated caspase-3 protein levels in heart tissue (gray value: 1.75 ± 0.25 vs. 1.00 ± 0.18, P<0.05) and an significant decline in the acetylation levels of histone H3 (gray value: 0.55 ± 0.18 vs. 1.00 ± 0.20, P<0.05) after major burn injury. VPA treatment significantly reduced the plasma CK-MB activities [(4 018.0 ± 388.3) U/L], activated caspase-3 protein levels in heart tissue (gray value: 1.33 ± 0.20), and raised the acetylation levels of histone H3 (gray value: 2.20 ± 0.23, all P<0.05). Survival analysis by Kaplan-Meier curves showed that the survival was improved after VPA treatment, and the survival rate was increased from 0 to 50% at 12 hours (P<0.05)., Conclusions: VPA can attenuate cardiac injury and improve survival in a rodent model of lethal burn injury. These protective effects may be due to its inhibitory effects on histone deacetylase and caspase-3 activation.