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We compare estimates of peer effects on worker output in laboratory experiments and field studies from naturally occurring environments. The mean study-level estimate of a change in a worker's productivity in response to an increase in a co-worker's productivity (γ) is γ̑ = 0.12 (SE = 0.03, n(studies) = 34), with a between-study standard deviation τ = 0.16. The mean estimated γ̑-values are close between laboratory and field studies (γ̑(lab) - γ̑(field) = 0.04, P = 0.55, n(lab) = 11, n(field) = 23), as are estimates of between-study variance τ(2) (τ̑(lab)(2) - τ̑(field)(2) = -0.003, P = 0.89). The small mean difference between laboratory and field estimates holds even after controlling for sample characteristics such as incentive schemes and work complexity (γ̑(lab) - γ̑(field) = 0.03, P = 0.62, n(samples) = 46). Laboratory experiments generalize quantitatively in that they provide an accurate description of the mean and variance of productivity spillovers.

U.S. income inequality has varied inversely with union density over the past hundred years. But moving beyond this aggregate relationship has proven difficult, in part because of limited microdata on union membership prior to 1973. We develop a new source of microdata on union membership dating back to 1936, survey data primarily from Gallup (N ≈ 980,000), to examine the long-run relationship between unions and inequality. We document dramatic changes in the demographics of union members: when density was at its mid-century peak, union households were much less educated and more nonwhite than other households, whereas pre-World-War-II and today they are more similar to nonunion households on these dimensions. However, despite large changes in composition and density since 1936, the household union premium holds relatively steady between ten and twenty log points. We then use our data to examine the effect of unions on income inequality. Using distributional decompositions, time series regressions, state-year regressions, as well as a new instrumental-variable strategy based on the 1935 legalization of unions and the World-War-II era War Labor Board, we find consistent evidence that unions reduce inequality, explaining a significant share of the dramatic fall in inequality between the mid-1930s and late 1940s.

A novel series of benzylamine, potassium channel openers (KCOs) is presented as part of our program toward designing new, bladder-selective compounds for the treatment of urge urinary incontinence (UUI). We have found that the in vitro potency of (R)-4-[3,4-dioxo-2-(1,2, 2-trimethyl-propylamino)-cyclobut-1-enylamino]-3-ethyl-benzo nitrile 1 in the relaxation of precontracted rat detrusor strips can also be obtained with cyanobenzylamine derivative 4 (IC(50) = 0.29 microM) (Figure 3). Addition of a 2-Cl substituted benzylamine moiety and changing the alkylamino substituent of 4 to a t-Bu amine gives 31 (IC(50) = 0.14 microM)-a compound with similar in vitro potency as 4 as well as relaxant activity on bladder smooth muscle in vivo when administered orally (31, ED(50) = 3 mg/kg) in a rodent model of bladder instability. Further modifications, particularly the replacement of the t-Bu amino substituent with a tert-amylamine, gave a similarly active compound 60 (IC(50) = 0.10 microM) which shows excellent in vivo efficacy (ED(50) = 0.6 mg/kg). Moreover, 60, 3-(2,4-dichloro-6-methyl-benzylamino)-4-(1, 1-dimethyl-propylamino)-cyclobut-3-ene-1,2-dione (WAY-151616), shows excellent tissue selectivity for bladder K channels over arterial tissue (60, MAP ED(20) = 100 mg/kg; selectivity: MAP ED(20)/bladder ED(50) = 166). Other manipulations of the benzylamino cyclobutenediones, acylation of the benzylamine, conversion of the benzylamine substituent to a benzamide, homologation of the benzylamine to a phenethylamine, and incorporation of a methyl group at the benzyl carbon, all led to substantial loss of in vitro activity, although some in vivo activity was maintained in the acylated analogues. Compound 60 represents an attractive candidate for development in the treatment of UUI.

At the point of pinch-off of an underwater air bubble, the speed of water rushing in diverges. Previous studies that assumed radial flow throughout showed that the local axial shape is two smoothly connected, slender cones that transition very slowly (logarithmically) to a cylindrical segment. Our simulations show that even with initially radial flow, a transient vertical flow develops with comparable speeds. Bernoulli pressure draws water into the singularity region while incompressibility forces it away from the neck minimum, generating significant vertical flows that rapidly slenderize and symmetrize the collapse region. This transition is due to a different mechanism, occurring much faster than previously expected. Vertical flows dictate the neck shape evolution.