The roles of serum vitamin D and tobacco smoke exposure in insomnia: a cross-sectional study of adults in the United States.

Aim: Tobacco smoke exposure and vitamin D (VD) status were both associated with insomnia. However, the combined effect of smoking and VD on insomnia has not been discussed. This study aimed to explore the role of VD in the association between tobacco smoke exposure and insomnia. Methods: Data on adults were extracted from the National Health and Nutrition Examination Surveys (NHANES) database in 2005-2008 for this cross-sectional study. Weighted univariate and multivariate logistic regression analyses were used to explore the associations between serum cotinine, serum VD, and insomnia. A surface diagram was drawn to reflect the effect of VD on the association between serum cotinine and insomnia. In addition, the potential regulating effect of VD in subgroups of smoking status was also performed. The evaluation index was odds ratios (ORs) with 95% confidence intervals (CIs). Results: Among the eligible participants, 1,766 had insomnia. After adjusting for covariates, we found that elevated serum cotinine levels were associated with higher odds of insomnia [OR = 1.55, 95% CI: (1.22, 1.97)]. However, the relationship between serum VD level and insomnia was not significant (P = 0.553). Higher serum cotinine levels were also associated with higher odds of insomnia [OR = 1.52, 95% CI: (1.17, 1.98)] when serum VD level was <75 nmol/L; however, this relationship became non-significant when serum VD concentration was elevated (P = 0.088). Additionally, the potential regulating effect of VD was also found in adults who were not smoking. Conclusion: VD may play a potential regulative role in the association between tobacco smoke exposure and insomnia. Further studies are needed to clarify the causal relationships between VD, tobacco smoke exposure, and insomnia.

Oxidation and ordering of fine structure of corn starch under an ultrahigh magnetic field.

In this study, corn starch (40 % moisture content) was placed in an ultra-high magnetic field(UMF)(5-20 T) to investigate the ordering and stabilization process under the magnetic field. With the increase of the intensity of UMF, C-OH and O-C-O were oxidized to O = C-OH and cross-linked to form ester bonds. When the UMF intensity was 15 T, the effect was the most significant with the ordered short-range structures formed; since the O = C-OR enhanced carbon skeleton structure, the crystallinity increased comparatively and amylose content reached the minimum value (15.32 ± 0.04 %). Additionally, UMF has a compressive effect on the void structure of A-type starch, and the average particle size decreased. RVA and DSC demonstrated that the UMF-treated starch had better thermal stability and shear resistance. This study suggested that UMF could serve as a prospective technique for starch product processing.