10,880 research outputs found
Incentivizing High-quality Content from Heterogeneous Users: On the Existence of Nash Equilibrium
We study the existence of pure Nash equilibrium (PNE) for the mechanisms used
in Internet services (e.g., online reviews and question-answer websites) to
incentivize users to generate high-quality content. Most existing work assumes
that users are homogeneous and have the same ability. However, real-world users
are heterogeneous and their abilities can be very different from each other due
to their diverse background, culture, and profession. In this work, we consider
heterogeneous users with the following framework: (1) the users are
heterogeneous and each of them has a private type indicating the best quality
of the content she can generate; (2) there is a fixed amount of reward to
allocate to the participated users. Under this framework, we study the
existence of pure Nash equilibrium of several mechanisms composed by different
allocation rules, action spaces, and information settings. We prove the
existence of PNE for some mechanisms and the non-existence of PNE for some
mechanisms. We also discuss how to find a PNE for those mechanisms with PNE
either through a constructive way or a search algorithm
Associations between Aquaglyceroporin Gene Polymorphisms and Risk of Stroke among Patients with Hypertension
Background: Dysregulations ofAQP7andAQP9were found to be related to lipid metabolism abnormality, which had been provento be one of the mechanisms of stroke. However, limited epidemiological studies explore the associations betweenAQP7andAQP9and the risk of stroke among patients with hypertension in China.
Aims: We aimed to investigate the associations between genetic variants in AQP7andAQP9and the risk of stroke among patients with hypertension, as well as to explore gene-gene andgene-environment interactions.
Methods: Baseline blood samples were drawn from 211 cases with stroke and 633 matched controls. Genomic DNA was extracted by a commercially available kit. Genotyping of 5 single nucleotide polymorphisms (SNPs) in AQP7 (rs2989924, rs3758269, and rs2542743) and AQP9 (rs57139208, rs16939881) was performed by the polymerase chain reaction assay with TaqMan probes.
Results: Participants with the rs2989924 GG genotype were found to be with a 1.74-fold increased risk of stroke compared to those with the AA+AG genotype, and this association remained significant after adjustment for potential confounders (odds ratio (OR): 1.74, 95% confidence interval (CI): 1.23-2.46). The SNP rs3758269 CC+TT genotype was found to be with a 33% decreased risk of stroke after multivariate adjustment (OR: 0.67, 95% CI: 0.45-0.99) compared to the rs3758269 CC genotype. The significantly increased risk of stroke was prominent among males, patients aged 60 or above, and participants who were overweight and with a harbored genetic variant in SNP rs2989924. After adjusting potential confounders, the SNP rs3758269 CT+TT genotype was found to be significantly associated with a decreased risk of stroke compared to the CC genotype among participants younger than 60 years old or overweight. No statistically significant associations were observed between genotypes of rs2542743, rs57139208, or rs16939881 with the risk of stroke. Neither interactions nor linkage disequilibrium had been observed in this study.
Conclusions: This study suggests that SNPs rs2989924 and rs3758269 are associated with the risk of stroke among patients with hypertension, while there were no statistically significant associations between rs2542743, rs57139208, and rs16939881 and the risk of stroke being observed
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