493 research outputs found
Vafa-Witten Estimates for Compact Symmetric Spaces
We give an optimal upper bound for the first eigenvalue of the untwisted
Dirac operator on a compact symmetric space G/H with rk G-rk H\le 1 with
respect to arbitrary Riemannian metrics. We also prove a rigidity statement.Comment: LaTeX, 11 pages. V2: Rigidity statement added, minor changes. To
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Information Overload and Confirmation Bias
We show that information overload contributes to confirmation bias. In an experiment, we vary the difficulty of information processing as subjects receive a sequence of signals of an unknown state. In the treatment condition, the preceding signal disappears as the next signal appears. In the control condition, the preceding signal remains visible. We find stronger confirmation bias among subjects in the treatment condition. Our results provide empirical support for models that emphasize the role of limited information processing in confirmation bias (Wilson (2014), Leung (2018), Jehiel and Steiner (2018))
How Wages Change: Micro Evidence from the International Wage Flexibility Project
How do the complex institutions involved in wage setting affect wage changes? The International Wage Flexibility Project provides new microeconomic evidence on how wages change for continuing workers. We analyze individuals’ earnings in 31 different data sets from sixteen countries, from which we obtain a total of 360 wage change distributions. We find a remarkable amount of variation in wage changes across workers. Wage changes have a notably non-normal distribution; they are tightly clustered around the median and also have many extreme values. Furthermore, nearly all countries show asymmetry in their wage distributions below the median. Indeed, we find evidence of both downward nominal and real wage rigidities. We also find that the extent of both these rigidities varies substantially across countries. Our results suggest that variations in the extent of union presence in wage bargaining play a role in explaining differing degrees of rigidities among countries.Wage setting, Wage change distributions, Downward nominal wage rigidity, Downward real wage rigidity
The interaction of labor markets and inflation: analysis of micro data from the International Wage Flexibility Project
Inflation can “grease” the wheels of economic adjustment in the labor market by relieving the constraint imposed by downward nominal wage rigidity, but not if there is also substantial downward real wage rigidity. At the same time, inflation can throw “sand” in the wheels of economic adjustment by degrading the value of price signals. A number of recent studies suggest that wage rigidity is much more important for business cycles and monetary policy than previously believed (see Erceg, Henderson and Levin, 2000, Smets and Wouters, 2003, and Hall, 2005). Thus, our results on how wage rigidity and other labor market imperfections vary between countries and how they are affected by the rate of inflation should be of considerable value in formulating monetary policy and conducting related research.
How wages change : micro evidence from the International Wage Flexibility Project
How do the complex institutions involved in wage setting affect wage changes? The International Wage Flexibility Project provides new microeconomic evidence on how wages change for continuing workers. We analyze individuals’ earnings in 31 different data sets from sixteen countries, from which we obtain a total of 360 wage change distributions. We find a remarkable amount of variation in wage changes across workers. Wage changes have a notably non-normal distribution; they are tightly clustered around the median and also have many extreme values. Furthermore, nearly all countries show asymmetry in their wage distributions below the median. Indeed, we find evidence of both downward nominal and real wage rigidities. We also find that the extent of both these rigidities varies substantially across countries. Our results suggest that variations in the extent of union presence in wage bargaining play a role in explaining differing degrees of rigidities among countriesWage setting, Wage change distributions, Downward nominal wage rigidity, Downward real wage rigidity
Spillovers of Prosocial Motivation: Evidence from an Intervention Study on Blood Donors
Spillovers of prosocial motivation can enhance the provision of public goods, and have implications for the cost-benefit analysis of policy interventions. We analyze a large-scale intervention among dyads of pre- registered blood donors. A quasi-random phone call provides the instrument for identifying endogenous and exogenous social interaction. The phone call has a strong effect on the recipient's propensity to donate. Between 40% and 44% of that behavioral impulse is transmitted within dyads due to motivational spillovers. This creates a significant social multiplier to policy interventions, with estimates ranging between 1.6 and 1.8. There is no evidence for exogenous social interaction
Control of template positioning during de novo initiation of RNA synthesis by the bovine viral diarrhea virus NS5B polymerase
The RNA-dependent RNA polymerase of the hepatitis C virus and the bovine viral diarrhea virus (BVDV) is able to initiate RNA synthesis de novo in the absence of a primer. Previous crystallographic datahave pointed to the existence of a GTP-specific binding site (G-site) that is located in the vicinity of the active site of the BVDV enzyme. Here we have studied the functional role of the G-site and present evidence to show that specific GTP binding affects the positioning of the template during de novo initiation. Following the formation of the first phosphodiester bond, the polymerase translocates relative to the newly synthesized dinucleotide, which brings the 5′-end of the primer into the G-site, releasing the previously bound GTP. At this stage, the 3′-end of the template can remain opposite to the 5′-end of the primer or be repositioned to its original location before RNA synthesis proceeds. We show that the template can freely move between the two locations, and both complexes can isomerize to equilibrium. These data suggest that the bound GTP can stabilize the interaction between the 3′-end of the template and the priming nucleotide, preventing the template to overshoot and extend beyond the active site during de novo initiation. The hepatitis C virus enzyme utilizes a dinucleotide primer exclusively from the blunt end; the existence of a functionally equivalent G-site is therefore uncertain. For the BVDV polymerase we showed that de novo initiation is severely compromised by the T320A mutant that likely affects hydrogen bonding between the G-site and the guanine base. Dinucleotide-primed reactions are not influenced by this mutation, which supports the notion that the G-site is located in close proximity but not at the active site of the enzyme. © 2006 by The American Society for Biochemistry and Molecular Biology, Inc
Safety and efficacy of dronedarone from clinical trials to real-world evidence: implications for its use in atrial fibrillation.
Efficacy and safety of dronedarone was shown in the ATHENA trial for paroxysmal or persistent atrial fibrillation (AF) patients. Further trials revealed safety concerns in patients with heart failure and permanent AF. This review summarizes insights from recent real-world studies and meta-analyses, including reports on efficacy, with focus on liver safety, mortality risk in patients with paroxysmal/persistent AF, and interactions of dronedarone with direct oral anticoagulants. Reports of rapidly progressing liver failure in dronedarone-prescribed patients in 2011 led to regulatory cautions about potential liver toxicity. Recent real-world evidence suggests dronedarone liver safety profile is similar to other antiarrhythmics and liver toxicity could be equally common with many Class III antiarrhythmics. Dronedarone safety concerns (increased mortality in patients with permanent AF) were raised based on randomized controlled trials (RCT) (ANDROMEDA and PALLAS), but comedication with digoxin may have increased the mortality rates in PALLAS, considering the dronedarone-digoxin pharmacokinetic (PK) interaction. Real-world data on apixaban-dronedarone interactions and edoxaban RCT observations suggest no significant safety risks for these drug combinations. Median trough plasma concentrations of dabigatran 110 mg during concomitant use with dronedarone are at acceptable levels, while PK data on the rivaroxaban-dronedarone interaction are unavailable. In RCTs and real-world studies, dronedarone significantly reduces AF burden and cardiovascular hospitalizations, and demonstrates a low risk for proarrhythmia in patients with paroxysmal or persistent AF. The concerns on liver safety must be balanced against the significant reduction in hospitalizations in patients with non-permanent AF and low risk for proarrhythmias following dronedarone treatment
Assessment of OMT-28, a synthetic analog of omega-3 epoxyeicosanoids, in patients with persistent atrial fibrillation: Rationale and design of the PROMISE-AF phase II study.
We designed a placebo controlled, double-blind, randomized, dose-finding phase II study on OMT-28 in the maintenance of sinus rhythm after electrical cardioversion (DCC) in patients with persistent atrial fibrillation (PROMISE-AF). OMT-28 is a first-in-class, synthetic analog of 17,18-epoxyeicosatetetraenoic acid, a bioactive lipid mediator generated by cytochrome P450 enzymes from the omega-3 fatty acid eicosapentaenoic acid. OMT-28 improves Ca2+-handling and mitochondrial function in cardiomyocytes and reduces pro-inflammatory signaling. This unique mode of action may provide a novel approach to target key mechanism contributing to AF pathophysiology. In a recent phase I study, OMT-28 was safe and well tolerated and showed favorable pharmacokinetics. The PROMISE-AF study (NCT03906799) is designed to assess the efficacy (primary objective), safety, and population pharmacokinetics (secondary objectives) of three different doses of OMT-28, administered once daily, versus placebo until the end of the follow-up period. Recruitment started in March 2019 and the study will include a total of 120 patients. The primary efficacy endpoint is the AF burden (% time with any AF), evaluated over a 13-week treatment period after DCC. AF burden is calculated based on continuous ECG monitoring using an insertable cardiac monitor (ICM). The primary efficacy analysis will be conducted on the modified intention-to-treat (mITT) population, whereas the safety analysis will be done on the safety population. Although ICMs have been used in other interventional studies to assess arrhythmia, PROMISE-AF will be the first study to assess antiarrhythmic efficacy and safety of a novel rhythm-stabilizing drug after DCC by using ICMs
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