Association Between Glucose Metabolism And Vascular Aging In Chinese Adults: A Cross-Sectional Analysis In The Tianning Cohort Study.

AIM: Fasting glucose has been associated with vascular aging, but the association between HbA1c and vascular aging has been limitedly studied in Chinese and other ethnic populations. We aimed to examine this association in a large sample of Chinese adults. METHODS: In the Tianning Cohort (N=5142), fasting glucose, HbA1c, carotid-femoral pulse wave velocity (cfPWV), and pulse pressure (PP) were measured. Vascular aging was defined as having the highest quartile level of cfPWV or PP. We applied quantile regression models to examine the association between glucose metabolism and vascular aging. RESULTS: The median cfPWV was significantly increased as increasing quintiles of fasting glucose (ß=0.14, P<0.001) and HbA1c (ß=0.07, P=0.0056), respectively. Per 1-mmol/L increment of fasting glucose was significantly associated with a higher risk of having vascular aging defined by cfPWV (OR=1.05, P=0.022), PP (OR=1.06, P=0.048), or either (OR=1.08, P=0.002). Similarly, per 1% increment of HbA1c was significantly associated with a higher risk of having vascular aging defined by cfPWV (OR=1.06, P=0.044), PP (OR=1.10, P=0.012), or either (OR=1.12, P=0.042). CONCLUSION: Glucose metabolism was significantly and positively associated with vascular aging in Chinese adults, but the causality is uncertain.

Element mixing distribution and structure feature of fusion zone in laser welding between different alloys and pure titanium.

OBJECTIVE: To study micro morphology and element-mixing distribution of different alloys welded in laser and analyze the feasibility of laser welding different alloys. METHODS: Alloys and titanium were matched into 4 groups: Au-Pt with Ni-Cr; Au-Pt with pure Ti; pure Ti with Ni-Cr; Ni-Cr with Co-Cr. They were welded in laser. Changes in metallography after hybridization of crystalline grain, ranges of heat-affected zone and pores were observed through SEM with ultra-thin windowed X-ray energy atlas. Meanwhile 10 testing points were chosen with area of 300 micro m x 900 micro m along the welding surface from the side A alloy to the side B alloy, than the element mixing distribution and tendency were analyzed with X-ray energy atlas. RESULTS: 1. Hybridization of different alloys: (l) in the group of Au-Pt with Ti, there was titanium element mixing into Au-Pt tissue gradually and evenly on the Au-Pt side of the interface without clear boundary and increasing in size of crystalline grain. However, there was titanium crystalline grain increasing in size, irregular morphology and small sacks on the titanium side with clear boundary. (2) in the group of Ni-Cr with Ti, there was mixing regularly, slow transition and interlocks between crystalline grains on the Ni-Cr side of the in terface. Poor transition, clear boundary and small cracks were observed on titanium side. (3) in the group of Co-Cr with Ni-Cr, there was good transition, obscure boundary on both sides resulting from network, cylinder and branch structure growing. 2. Element-mixing distribution of different alloys. In fusion zone, the metal elements in matched groups mixed well and hybridized into new alloys except titanium blocks. The location of wave peak depended on the composition of alloys. Most of elements were from the alloy far from the fusion zone. CONCLUSION: The hybridization between pure titanium and any other alloys is not good The effect of laser welding different alloys is ideal except with pure titanium.