Author Correction: Drivers of seedling establishment success in dryland restoration efforts

1 Pág. Correción errata.In the version of this Article originally published, the surname of author Tina Parkhurst was incorrectly written as Schroeder. This has now been corrected.Peer reviewe

Pulsed coherent effects in atomic sodium

We show that gain in a noninverted medium of atomic sodium exists in the transient regime.</jats:p

Computer modeling of lasing without inversion in atomic samarium

Remarkable effects are predicted in a coherently prepared atomic medium. These include gain without inversion and high index of refraction with zero absorption.1 Atomic samarium in a magnetic field is an attractive system for the experimental realization of these effects. We have modeled the behavior of this system for a strong, coherence-inducing pump and a weak probe. We calculate probe eigenpolarizations and the associated susceptibilities as a function of probe frequency using realistic values for oscillator strengths, damping rates, and number density but not including Doppler broadening. This eigenpolarization approach is an advance over previous treatments of these effects. We demonstrate that under certain conditions gain without inversion and high index of refraction still occur when this model is used. Furthermore, under certain conditions the probe exhibits double refraction. The current model assumes that the pump propagates without modification. The next step will be to model the pump propagation more realistically.</jats:p

Noncolinear optical parametric oscillator for broadband nanosecond pulse-burst CARS diagnostics in gases

Demonstration of broadband nanosecond coherent anti-Stokes Raman scattering (CARS) using a burst-mode-pumped noncolinear optical parametric oscillator (NOPO) has been achieved at a pulse repetition rate of 40 kHz. The NOPO is pumped with the 355-nm output of a burst-mode Nd:YAG laser at 50 mJ/pulse for 45 pulses and produces an output centered near 607 nm, with a bandwidth of 370 cm−1 at energies of 5 mJ/pulse. A planar BOXCARS phase matching scheme uses the broadband NOPO output as the Stokes beam and the narrowband 532-nm burst-mode output for the two CARS pump beams for single-laser-shot nitrogen thermometry in near adiabatic H2/air flames at temperatures up to 2200 K.</jats:p

Food-Foraging Behavior of Male Euglossini (Hymenoptera: Apidae): Vagabonds or Trapliners?

The nectar-foraging behavior of male euglossine bees (Hymenoptera: Apidae) was studied at a population of Calathea latifolia (Marantaceae) on Barro Colorado Island, Panama, for two weeks. Several marked males of Exaerete smaragdina and Euglossa imperialis foraged at C. latifolia on a daily basis. Immigration rates were low, and the site fidelity of bees was high. Selection of inflorescences by the marked individuals was not random. The bees learned specific locations of inflorescences at which they consistently foraged and ignored nearby inflorescences. However, not all inflorescences in a bee\u27s repertoire were included in each foraging bout. The sequence of inflorescences visited was not the same within or between days nor were the foraging routes uni-directional. Foraging bouts of both male and female bees did not conform to rigid time schedules. Thus, male euglossine bees are not necessarily as transient and vagabond as previously portrayed. Those males that are site-constant forage in a fashion reminiscent of the traplining behavior once described for females. We propose that euglossine bees change their foraging habits as shifts in resource availability and dispersion occur