THE IMPACT OF LOCAL LABOR MARKET CONDITIONS ON THE OFF-FARM EARNINGS OF FARM OPERATORS

Local labor market characteristics are theoretically relevant to the determination of off-farm earnings of farm operators, but the empirical analysis of these effects has been hindered by a lack of appropriate data. This study employs the new census public use micro-data sample, PUMS-D, to investigate the effect of local labor market characteristics on off-farm earnings of farm operators. The PUMS-D data allow local characteristics to be defined on a labor market area basis, rather than on a political boundary basis. For a sample of Georgia farm operators, local labor market size, unemployment rates, and industrial structure were found to have significant impacts on off-farm employment and earnings.Labor and Human Capital,

Energy flows in vibrated granular media

We study vibrated granular media, investigating each of the three components of the energy flow: particle-particle dissipation, energy input at the vibrating wall, and particle-wall dissipation. Energy dissipated by interparticle collisions is well estimated by existing theories when the granular material is dilute, and these theories are extended to include rotational kinetic energy. When the granular material is dense, the observed particle-particle dissipation rate decreases to as little as 2/5 of the theoretical prediction. We observe that the rate of energy input is the weight of the granular material times an average vibration velocity times a function of the ratio of particle to vibration velocity. `Particle-wall' dissipation has been neglected in all theories up to now, but can play an important role when the granular material is dilute. The ratio between gravitational potential energy and kinetic energy can vary by as much as a factor of 3. Previous simulations and experiments have shown that E ~ V^delta, with delta=2 for dilute granular material, and delta ~ 1.5 for dense granular material. We relate this change in exponent to the departure of particle-particle dissipation from its theoretical value.Comment: 19 pages revtex, 10 embedded eps figures, accepted by PR

Determining the Maternal and Fetal Cellular Immunologic Contributions in Preterm Deliveries With Clinical or Subclinical Chorioamnionitis

Objective: Our purpose was to determine the maternal and fetal polymorphonuclear contributions to preterm histologic chorioamnionitis and whether this response differs in clinical chorioamnionitis when compared to cases without clinical chorioamnionitis

Who is in the transition gap? Transition from CAMHS to AMHS in the Republic of Ireland

Objective: The ITRACK study explored the process and predictors of transition between Child and Adolescent Mental Health Services (CAMHS) and Adult Mental Health Services (AMHS) in the Republic of Ireland. Method: Following ethical approval, clinicians in each of Ireland's four Health Service Executive (HSE) areas were contacted, informed about the study and invited to participate. Clinicians identified all cases who had reached the transition boundary (i.e. upper age limit for that CAMHS team ) between January and December 2010. Data were collected on clinical and socio-demographic details and factors that informed the decision to refer or not refer to AMHS and case notes were scrutinised to ascertain the extent of information exchanged between services during transition

Self-diffusion in granular gases

The coefficient of self-diffusion for a homogeneously cooling granular gas changes significantly if the impact-velocity dependence of the restitution coefficient $\epsilon$ is taken into account. For the case of a constant $\epsilon$ the particles spread logarithmically slow with time, whereas the velocity dependent coefficient yields a power law time-dependence. The impact of the difference in these time dependences on the properties of a freely cooling granular gas is discussed.Comment: 6 pages, no figure

Zygomaticomaxillary suture maturation: A predictor of maxillary protraction? Part I ‐ A classification method

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136728/1/ocr12143.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136728/2/ocr12143_am.pd

Shock-Like Dynamics of Inelastic Gases

We provide a simple physical picture which suggests that the asymptotic dynamics of inelastic gases in one dimension is independent of the degree of inelasticity. Statistical characteristics, including velocity fluctuations and the velocity distribution are identical to those of a perfectly inelastic sticky gas, which in turn is described by the inviscid Burgers equation. Asymptotic predictions of this continuum theory, including the t^{-2/3} temperature decay and the development of discontinuities in the velocity profile, are verified numerically for inelastic gases.Comment: 4 pages, 5 figures, revte

Temperature scaling in a dense vibro-fluidised granular material

The leading order "temperature" of a dense two dimensional granular material fluidised by external vibrations is determined. An asymptotic solution is obtained where the particles are considered to be elastic in the leading approximation. The velocity distribution is a Maxwell-Boltzmann distribution in the leading approximation. The density profile is determined by solving the momentum balance equation in the vertical direction, where the relation between the pressure and density is provided by the virial equation of state. The predictions of the present analysis show good agreement with simulation results at higher densities where theories for a dilute vibrated granular material, with the pressure-density relation provided by the ideal gas law, are in error. The theory also predicts the scaling relations of the total dissipation in the bed reported by McNamara and Luding (PRE v 58, p 813).Comment: ReVTeX (psfrag), 5 pages, 5 figures, Submitted to PR

Energy non-equipartition in systems of inelastic, rough spheres

We calculate and verify with simulations the ratio between the average translational and rotational energies of systems with rough, inelastic particles, either forced or freely cooling. The ratio shows non-equipartition of energy. In stationary flows, this ratio depends mainly on the particle roughness, but in nonstationary flows, such as freely cooling granular media, it also depends strongly on the normal dissipation. The approach presented here unifies and simplifies different results obtained by more elaborate kinetic theories. We observe that the boundary induced energy flux plays an important role.Comment: 4 pages latex, 4 embedded eps figures, accepted by Phys Rev

Identification and distribution of leatherjackets (Tipula spp.) in the Republic of Ireland

peer-reviewedThe soil-dwelling larval stage of crane flies, commonly known as leatherjackets, are classified as agricultural pests in Europe, and pests of turf in North America and Canada. They cause significant damage and yield loss in many cropping systems through their feeding on plant roots and stems at ground level. The effective chemical control for these pests, chlorpyrifos (available since 1965), was prohibited across Europe in 2019. This has left severely restricted control options for growers. Unlike Northern Ireland and Great Britain, no leatherjacket surveys or routine identifications have been conducted across Ireland. Therefore, the leatherjacket species of agronomic importance has not been confirmed. Since lifecycles, feeding behaviour and damage periods differ between species, identifying the most common species is a vital first step in any pest management strategy. Here we report key findings from a 2-yr structured survey of Irish crops, conducted in 2019 and 2021, where 135 sites were sampled. Both grassland and cereal crops were inspected. Soil cores and soil samples were collected and larval abundance determined. The European crane fly, Tipula paludosa Meigen, accounted for approximately 70% of larvae collected and identified (n = 337). In 2019, 40% of grasslands exceeded the threshold of 1 million larvae/ha, while only 3.3% of cereal fields were over the threshold of 600,000 larvae/ha. These results indicate that agricultural grasslands in Ireland have the potential to be significantly impacted by leatherjacket damage, although this may vary temporally and geographically across the island. Without effective control options, yield losses will be highly probable