Robust Mendelian randomization in the presence of residual population stratification, batch effects and horizontal pleiotropy

Mendelian Randomization (MR) studies are threatened by population stratification, batch effects, and horizontal pleiotropy. Although a variety of methods have been proposed to mitigate those problems, residual biases may still remain, leading to highly statistically significant false positives in large databases. Here we describe a suite of sensitivity analysis tools that enables investigators to quantify the robustness of their findings against such validity threats. Specifically, we propose the routine reporting of sensitivity statistics that reveal the minimal strength of violations necessary to explain away the MR results. We further provide intuitive displays of the robustness of the MR estimate to any degree of violation, and formal bounds on the worst-case bias caused by violations multiple times stronger than observed variables. We demonstrate how these tools can aid researchers in distinguishing robust from fragile findings by examining the effect of body mass index on diastolic blood pressure and Townsend deprivation index.

Reports of the AAAI 2019 Spring Symposium Series

The AAAI 2019 Spring Series was held Monday through Wednesday, March 25–27, 2019 on the campus of Stanford University, adjacent to Palo Alto, California. The titles of the nine symposia were Artificial Intelligence, Autonomous Machines, and Human Awareness: User Interventions, Intuition and Mutually Constructed Context; Beyond Curve Fitting — Causation, Counterfactuals and Imagination-Based AI; Combining Machine Learning with Knowledge Engineering; Interpretable AI for Well-Being: Understanding Cognitive Bias and Social Embeddedness; Privacy- Enhancing Artificial Intelligence and Language Technologies; Story-Enabled Intelligence; Towards Artificial Intelligence for Collaborative Open Science; Towards Conscious AI Systems; and Verification of Neural Networks.

All-versus-nothing nonlocality test of quantum mechanics by two-photon hyperentanglement

We report the experimental realization and the characterization of polarization and momentum hyperentangled two-photon states, generated by a new parametric source of correlated photon pairs. By adoption of these states an "all-versus-nothing" test of quantum mechanics was performed. The two-photon hyperentangled states are expected to find at an increasing rate a widespread application in state engineering and quantum information.

[The prevention of nitrate tolerance in angina patients treated with transdermal nitroglycerin: a comparison of 2 therapeutic regimens (therapeutic outlook versus dosage reduction)]

We studied the long-term antianginal and anti-ischemic effects of two dosage regimens designed to prevent tolerance to transdermal nitroglycerin (TNTG): (1) 10 mg TNTG applied for 16 h with a 'nitrate-free' interval of 8 h; (2) 10 mg TNTG applied for 16 h followed by a 'nitrate-low' interval of 5 mg applied for 8 h. 129 patients completing a 3-month study period were evaluated by repeated exercise tests. Both regimens significantly increased maximum exercise duration at 3 months, from 699.1 +/- 23.4 to 833 +/- 21.9 s and from 686.1 +/- 20 to 789.6 +/- 22.6 s, respectively, reduced the number of patients with 1 mm S-T segment depression and increased the time duration to 1 mm S-T segment depression. Marked reductions in anginal attacks was observed in both groups: from 6.5 to 0.15 attacks per week and from 6.0 to 0.15 attacks per week, respectively. No statistically significant differences were found between the groups, and both regimens were well tolerated. In conclusion, our results demonstrate sustained antianginal efficacy, without tolerance, of either 'nitrate-free' of 'nitrate-low' interval therapy with transdermal nitroglycerin.