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To change the situation of shape memory polymers (SMPs) that can only remember very few shapes and enable discretional morphing for practical application, the authors report a reversible stepless multiple SMP derived from ultrahigh molecular weight polyethylene (UHMWPE). As the crystals of semi‐crystalline polymers are assembled by those with slightly different melting temperatures, and each type of crystal can remember a single shape, the crystalline region of UHMWPE is allowed to remember plenty of temporary shapes after programming. Changing the temperature of the programmed polymer within the melting/crystallization temperature ranges would lead to releasing/recovery of the memorized temporary shapes. Accordingly, multiple shape memory effects can be easily realized without an elaborate design of material structure and training process in advance as before. The temperature‐dependent adjustability of the analog capacitor and soft lens with embedded programmed UHMWPE as actuators, characterized by the continuous/random/proportional responsivity, further reveals the utilization prospects of the controllable reversible stepless discretionary morphing effect. Moreover, the maximum work density of the programmed UHMWPE is found to be 210 kJ/m3, which is more than 10 times of piezoelectric ceramics, so that it can serve as a proof‐of‐concept mechanical driver for reversibly pumping of ethanediol‐droplet upon heating/cooling. [ABSTRACT FROM AUTHOR]

Background: Pancreatic ductal adenocarcinoma (PDAC) is a devastatingly malignant tumor with a high mortality. However, current strategies to treat PDAC generally have low efficacy and high side-effects, therefore, effective treatment against PDAC remains an urgent need. Results: We report a semiconducting polymer nano-radiopharmaceutical with intrinsic photothermal capability and labeling with therapeutic radioisotope 177Lu (177Lu-SPN-GIP) for combined radio- and photothermal therapy of pancreatic tumor. 177Lu-SPN-GIP endowed good stability at physiological conditions, high cell uptake, and long retention time in tumor site. By virtue of combined radiotherapy (RT) and photothermal therapy (PTT), 177Lu-SPN-GIP exhibited enhanced therapeutic capability to kill cancer cells and xenograft tumor in living mice compared with RT or PTT alone. More importantly, 177Lu-SPN-GIP could suppress the growth of the tumor stem cells and reverse epithelial mesenchymal transition (EMT), which may greatly reduce the occurrence of metastasis. Conclusion: Such strategy we developed could improve therapeutic outcomes over traditional RT as it is able to ablate tumor with relatively lower doses of radiopharmaceuticals to reduce its side effects. [ABSTRACT FROM AUTHOR]