The serial mediating effects of learning motivation and learning engagement on the relationship between gen AI literacy and EFL perceived proficiency among vocational students.

Cerebrovascular accidents (CVA) remain a leading cause of mortality and disability worldwide (). Carotid artery calcification, a marker of advanced atherosclerosis, is strongly associated with increased stroke risk and adverse cardiovascular outcomes (). However, vascular calcification represents only one component of cerebrovascular risk biology and does not fully capture thrombosis-related mechanisms, endothelial dysfunction, or plaque instability, which are also critical determinants of stroke occurrence and progression (). While traditional risk factors are well-established, emerging evidence suggests that dietary patterns and gut microbiota composition play critical roles in atherosclerotic disease pathogenesis (). The gut microbiota functions as a metabolically active organ influencing systemic inflammation, immune regulation, and metabolic homeostasis. Dysbiosis—characterized by reduced microbial diversity and elevated Firmicutes/Bacteroidetes (F/B) ratio—has been implicated in multiple cardiometabolic disorders (, ). Diet serves as a primary modulator of gut microbiota composition, with certain patterns promoting eubiosis and beneficial metabolite production, while others favor dysbiotic states and pro-inflammatory metabolite generation (). Trimethylamine N-oxide (TMAO), produced through hepatic oxidation of gut bacteria-derived trimethylamine from dietary choline, phosphatidylcholine, and L-carnitine, has emerged as an important cardiovascular disease mediator (). Elevated TMAO levels are associated with atherosclerotic plaque development and vascular calcification (, ). However, while TMAO-cardiovascular outcome relationships are established, the extent to which dietary patterns can modulate TMAO production and subsequently influence vascular calcification remains incompletely understood. Short-chain fatty acids (SCFAs)—including butyrate, propionate, and acetate—represent another critical class of gut microbiota-derived metabolites with predominantly beneficial effects (). Produced through bacterial fermentation of dietary fiber, SCFAs exert anti-inflammatory effects, improve intestinal barrier integrity, and modulate immune function (). Fiber-rich, plant-based dietary patterns promote SCFA production, potentially counteracting pro-inflammatory and pro-atherogenic pathways ().