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Chronic non-communicable diseases have increased worldwide, threatening not only the health of individuals but also social stability. Global studies have identified behavioral, environmental, and stress-related factors that account for a substantial amount of variance in these diseases. Identification of these relatively easy modifiable lifestyle factors holds great potential for the development of global prevention strategies in order to improve health and thereby promote economic, ecologic, and social sustainability worldwide.  相似文献   
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Polymerizations of l-lactide catalyzed either by neat SnCl2 or by SnCl2?+?difunctional cocatalysts were conducted in bulk at 180, 160 and 140 °C with variation of the Lac/Cat ratio and time. With neat SnCl2 poly(L-lactide) having weight average molecular weights (uncorrected Mw’s) up to 190 000 g mol?1 were obtained mainly consisting of linear chains. Addition of salicylic acid or 1,1-bisphenol yielded a higher fraction of cyclic polylactides but lower molecular weights. Furthermore, SnCl2 was compared with Bu2SnCl2 and various other metal chlorides and the best results were obtained with SnCl2. With ethyl L-lactate as initiator SnCl2-catalyzed ROPs were performed at 120 °C and the lac/initiator ratio was varied. All these experiments were conducted under conditions allowing for comparison with ROPs catalyzed with neat Sn(II)-2-ethyhexanoate. Such a comparison was also performed with ε-caprolactone as monomer.

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