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High altitude and strong ultraviolet radiation in Qinghai Tibet Plateau induces the brittleness and hardening of asphalt, which leads to temperature cracks, pits and other diseases of asphalt pavement. In this paper, the accelerated UV aging test of rubber asphalt was carried out by simulating the UV radiation intensity in Xining, Qinghai Province, and the rheological properties and microstructure changes of rubber asphalt were analyzed. The results show that the complex modulus of rubber asphalt increases exponentially with the extension of UV aging time. The phase angle of rubber asphalt decreases linearly with UV aging, and the deformation recovery performance of rubber asphalt increases; UV radiation has the most significant effect on the micro morphology of rubber asphalt. With the further extension of UV aging time, micro cracks are formed in rubber asphalt, and the low-temperature crack resistance and fatigue failure resistance of rubber asphalt are gradually reduced.

Previous genome-wide association studies have demonstrated that single nucleotide polymorphisms in T‑box (TBX)5 are associated with increased susceptibility to atrial fibrillation (AF), and a recent study has causally linked a TBX5 mutation to atypical Holt-Oram syndrome and paroxysmal AF. However, the prevalence and spectrum of TBX5 mutations in patients with AF remain to be elucidated. In the present study, a cohort of 190 unrelated patients with idiopathic AF were prospectively recruited, with 400 unrelated healthy individuals recruited as controls. The coding exons and flanking introns of the TBX5 gene were sequenced in the participants. The functional characteristics of the mutant TBX5 were delineated in contrast with its wild‑type counterpart using a dual‑luciferase reporter assay system. As a result, a novel heterozygous TBX5 mutation, p.P132S, was identified in an index patient with AF, with a mutational prevalence of ~0.53%. Genetic analysis of the proband's family showed that the mutation co‑segregated with AF, and was transmitted in an autosomal dominant pattern. The missense mutation was absent in the 800 control chromosomes, and the altered amino acid was completely evolutionarily conserved across species. Functional analyses revealed that the mutant TBX5 had significantly reduced transcriptional activity. Furthermore, the mutation markedly decreased the synergistic activation between TBX5 and NK2 homeobox 5, another transcription factor which has been causatively linked to AF. The present study was the first, to the best of our knowledge, to report on the association between a TBX5 loss‑of‑function mutation and increased susceptibility to AF. These results provide novel insight into the molecular mechanism underpinning AF, and have potential implications in the development of novel prophylactic and therapeutic strategies for AF, the most common form of sustained cardiac arrhythmia.

Parasitic plants are destructive agricultural pests. Today, parasitic plants have been recognized as serious pests causing considerable economic damage on crop and woods in China. Parasites are among the most destructive weeds known, and more and more people begin to pay more attention to the relationship between parasitic plant and host. Two cistanches and their hosts were analyzed and characterized by ICP-AES. The contents of K, P, Na, Ca, Mg, Fe, B, Cu, Zn, Al and Mn in Tamarix chinensis, Haloxylon ammodendron, Cistanche deserticola and Cistanche tubulosa were determined. The results showed that the spectra of main elements of the two cistanches and their hosts are similar, but the content of each element is different. The content of K, P, N and Ca is higher than other element, The content of K and P in Cistanche deserticola and Cistanche tubulosa is higher than the content of theirs hosts. The present study provides a new scientific foundation for further study and general application of parasitic plant.