3,194 research outputs found
Oribatid assemblies of tropical high mountains on some points of the “Gondwana-Bridge” – a case study
This work is the first part of a series of studies, which introduces the methodological possibilities of coenological and zoogeographical indication and – following the climate, vegetation and elevation zones – the pattern-describing analysis of the main Oribatid sinusia of the world explored till our days.This current work is a case-study, which displays the comparison of 9 examination sites from 3
different geographical locations. On each location, three vegetation types have been examined: a plain
rain-forest, a mossforest and a mountainous paramo. Analyses are based on the hitherto non-published
genus-level database and coenological tables of the deceased János Balogh professor. Occurrence of 18
genera is going to be published as new data for the given zoogeographical region
Morse, Donald E., Csilla Bertha, and Mária Kurdi (Eds) Brian Friel’s Dramatic Artistry. ’The Work Has Value.’
Morse, Donald E., Csilla Bertha, and Mária Kurdi (Eds) Brian Friel’s Dramatic Artistry. ’The Work Has Value.’ Dublin: Carysfort Press, 2006, 342 pp
Bounding sup-norms of cusp forms of large level
Let f be an -normalized weight zero Hecke-Maass cusp form of square-free
level N, character and Laplacian eigenvalue . It is
shown that , from which the hybrid
bound (for some
) is derived. The first bound holds also for where F
is a holomorphic cusp form of weight k with the implied constant now depending
on k.Comment: version 3: substantially revised versio
Galaxy bimodality versus stellar mass and environment
We analyse a z<0.1 galaxy sample from the Sloan Digital Sky Survey focusing
on the variation of the galaxy colour bimodality with stellar mass and
projected neighbour density Sigma, and on measurements of the galaxy stellar
mass functions. The characteristic mass increases with environmental density
from about 10^10.6 Msun to 10^10.9 Msun (Kroupa IMF, H_0=70) for Sigma in the
range 0.1--10 per Mpc^2. The galaxy population naturally divides into a red and
blue sequence with the locus of the sequences in colour-mass and
colour-concentration index not varying strongly with environment. The fraction
of galaxies on the red sequence is determined in bins of 0.2 in log Sigma and
log mass (12 x 13 bins). The red fraction f_r generally increases continuously
in both Sigma and mass such that there is a unified relation: f_r =
F(Sigma,mass). Two simple functions are proposed which provide good fits to the
data. These data are compared with analogous quantities in semi-analytical
models based on the Millennium N-body simulation: the Bower et al. (2006) and
Croton et al. (2006) models that incorporate AGN feedback. Both models predict
a strong dependence of the red fraction on stellar mass and environment that is
qualitatively similar to the observations. However, a quantitative comparison
shows that the Bower et al. model is a significantly better match; this appears
to be due to the different treatment of feedback in central galaxies.Comment: 19 pages, 17 figures; accepted by MNRAS, minor change
First Cluster results of the magnetic field structure of the mid- and high-altitude cusps
International audienceMagnetic field measurements from the four Cluster spacecraft from the mid- and high-altitude cusp are presented. Cluster underwent two encounters with the mid-altitude cusp during its commissioning phase (24 August 2000). Evidence for field-aligned currents (FACs) was seen in the data from all three operating spacecraft from northern and southern cusps. The extent of the FACs was of the order of 1 RE in the X-direction, and at least 300 km in the Y-direction. However, fine-scale field structures with scales of the order of the spacecraft separation (300 km) were observed within the FACs. In the northern crossing, two of the spacecraft appeared to lie along the same magnetic field line, and observed very well matched signals. However, the third spacecraft showed evidence for structuring transverse to the field on scales of a few hundred km. A crossing of the high-altitude cusp from 13 February 2001 is presented. It is revealed to be a highly dynamic structure with the boundaries moving with velocities ranging from a few km/s to tens of km/s, and having structure on timescales ranging from less than one minute up to several minutes. The cusp proper is associated with the presence of a very disordered magnetic field, which is entirely different from the magnetosheath turbulence
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