Social Functioning of Children and Their Parents: Are They Related?

This study examined whether parents' social support was related to their children's peer acceptance and likability. The moderating role of the parent's and the child's gender was also examined. Father (N = 146-150) and mother (N = 201) reports of social support and peer reports of peer acceptance were obtained from 107 boys and 96 girls (7.92-16.76 years, M = 11.77). Aspects of fathers' and mothers' social support were observed to be differentially correlated with their children's friendships and likability. While fathers' social support was moderately correlated with their children's friendships, mothers' social support was not. The implications of these findings for the role of fathers in children's social functioning are discussed

Sediment disturbance caused by a suspension-feeding tubular agglutinated foraminifer

We report the occurrence of in-situ sediment disturbance caused by a specimen of Rhabdammina observed in life position on the 1991 Mt. Pinatubo ash layer in the abyssal South China Sea. The specimen extracts sediment grains from the ash layer to build its agglutinated test, causing a depression, or “moat” to form around the base of the specimen. We suspect that such fine-scale disturbance caused by large, erect tubular foraminifera is a common feature of the fossil record in deep-sea settings

A tubular protozoan predator: a burrow selectively filled with tubular agglutinated protozoans (Xenophyophorea, Foraminifera) in the abyssal South China Sea

We report the occurrence of an unusual agglutinated protozoan-filled burrow recovered in a box core collected in 1998 from a depth of 2496 m in the South China Sea. The onion-shaped burrow occurring some 8 cm beneath the sediment surface was packed full with specimens of xenophyophoreans and foraminifera dominated by a single genus (Aschemonella) that had been living on the surface of the 1991 Mt. Pinatubo ash layer. This selective scavenging of epibenthic tubular agglutinated protozoans contributes to the patchiness of the benthic fauna on the sea floor. Because the tubular protozoans selectively agglutinate mafic mineral grains from the volcanic ash, two levels of biological scavenging are involved with the redistribution of these volcanic grains

Economies of Scope in European Railways: An Efficiency Analysis

In the course of railway reforms at the end of the last century, European na- tional governments, as well the EU Commission, decided to open markets and to separate railway networks from train operations. Vertically integrated railway com- panies argue that such a separation of infrastructure and operations would diminish the advantages of vertical integration and would therefore not be suitable to raise economic welfare. In this paper, we conduct a pan-European analysis to investi- gate the performance of European railways with a particular focus on economies of scope associated with vertical integration. We test the hypothesis that integrated railways realize economies of joint production and, thus, produce railway services on a higher level of efficiency. To determine whether joint or separate production is more efficient we apply an innovative Data Envelopment Analysis super-efficiency bootstrapping model which relates the efficiency for integrated production to a vir- tual reference set consisting of the separated production technology and which is applicable to other network industries as energy and telecommunication as well. Our findings are that for a majority of European Railway companies economies of scope exist.Efficiency, Vertical Integration, Railway Industry

Are Halo and Galaxy Formation Histories Correlated?

The properties of dark matter halos, including mass growth, correlate with larger scale environment at fixed mass, an effect known as assembly bias. However, whether this environmental dependence manifests itself in galaxy properties remains unclear. We apply a group-finding algorithm to DR7 of the SDSS to estimate the halo mass of each galaxy and to decompose galaxies into those that exist at the centers of distinct halos and those that orbit as satellites within larger halos. Using the 4000-A break as a measure of star formation history, we examine the correlation between the quenched fraction of galaxies, f_q, and large-scale environment, rho. At all galaxy magnitudes, there is a positive, monotonic relationship between f_q and rho. We use the group catalog to decompose this correlation into the contribution from central and satellite galaxies as a function of halo mass. Because satellites are more likely to be quenched than central galaxies, the observed f_q-rho correlation is primarily due to variations of the halo mass function with environment, which causes a larger fraction of satellite galaxies at high rho. For low-mass central galaxies (Mgal <~ 10^10.0 Msol/h^2), there is no correlation between f_q and rho. These results are inconsistent with the strong assembly bias of dark matter halos seen in this mass regime if recent galaxy growth at all correlates with recent halo growth, as we demonstrate through a high resolution N-body simulation. We also find that the mean stellar age of quenched central galaxies is independent of rho at fixed Mgal, while the formation times of low mass halos vary significantly. We conclude that the processes that halt the star formation of low mass central galaxies are not correlated to the formation histories of their host halos, and old galaxies do not reside preferentially in old halos. (Abridged)Comment: 21 pages, submitted to MNRA

Direct Scattering for the Benjamin-Ono Equation with Rational Initial Data

We compute the scattering data of the Benjamin-Ono equation for arbitrary rational initial conditions with simple poles. Specifically, we obtain explicit formulas for the Jost solutions and eigenfunctions of the associated spectral problem, yielding an Evans function for the eigenvalues and formulas for the phase constants and reflection coefficient.Comment: 16 Pages, 2 Figure