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Photometric modeling of a cometary nucleus: taking Hapke modeling to the limit
Ecological and physical characteristics of the Te Awa O Katapaki Stream, Flagstaff, Waikato
1. The fish, macroinvertebrates, aquatic vegetation, and water quality indicate that the Te Awa O Katapaki Stream is an unpolluted, pastureland stream that is typical of the Waikato region.
2. The stream has very high nutrient concentrations that probably result from the dairy farming upstream.
3. The fish fauna is dominated by the native shortfinned eels. The presence of the migratory common smelt indicates that swimming fish species also have free access to the stream from the Waikato River.
4. Fish of high conservation value, such as giant or banded kokopu (Galaxias argenteus or G. fasciatus) were absent, which is predictable given the warm, unshaded nature of the stream.
5. Fish and invertebrates would soon recolonise the restored stream following any work in the streambed
The 1981 Argentina ground data collection
Over 600 fields in the corn, soybean and wheat growing regions of the Argentine pampa were categorized by crop or cover type and ancillary data including crop calendars, historical crop production statistics and certain cropping practices were also gathered. A summary of the field work undertaken is included along with a country overview, a chronology of field trip planning and field work events, and the field work inventory of selected sample segments. LANDSAT images were annotated and used as the field work base and several hundred ground and aerial photographs were taken. These items along with segment descriptions are presented. Meetings were held with officials of the State Secretariat of Agriculture (SEAG) and the National Commission on Space Investigations (CNIE), and their support to the program are described
Mortality associated with avian reovirus infection in a free-living magpie (Pica pica) in Great Britain
Avian reoviruses (ARVs) cause a range of disease presentations in domestic, captive and free-living bird species. ARVs have been reported as a cause of significant disease and mortality in free-living corvid species in North America and continental Europe. Until this report, there have been no confirmed cases of ARV-associated disease in British wild birds
Photoproduction of the meson on the proton at large momentum transfer
The differential cross section, for meson exclusive
photoproduction on the proton above the resonance region ( GeV) was
measured up to a momentum transfer GeV using the CLAS detector at
Jefferson Laboratory. The channel was identified by detecting a proton
and in the final state and using the missing mass technique. While the
low momentum transfer region shows the typical diffractive pattern expected
from Pomeron and Reggeon exchange, at large the differential cross section
has a flat behavior. This feature can be explained by introducing quark
interchange processes in addition to the QCD-inspired two-gluon exchange.Comment: 5 pages, 5 figure
Design and Implementation of a Python-Based Active Network Platform for Network Management and Control
Active networks can provide lightweight solutions for network management-related tasks. Specific requirements for these tasks have to be met, while at the same time several issues crucial for active networks can be solved rather easily. A system addressing especially network management was developed and implemented. It provides a flexible environment for rapid development using the platform-independent programming language Python, and also supports platform dependent native code. By allowing to add new functions to network devices it improves the performance of Internet routers, and simplifies the introduction and maintenance of new services
A z=0.9 supercluster of X-ray luminous, optically-selected, massive galaxy clusters
We report the discovery of a compact supercluster structure at z=0.9. The
structure comprises three optically-selected clusters, all of which are
detected in X-rays and spectroscopically confirmed to lie at the same redshift.
The Chandra X-ray temperatures imply individual masses of ~5x10^14 Msun. The
X-ray masses are consistent with those inferred from optical--X-ray scaling
relations established at lower redshift. A strongly-lensed z~4 Lyman break
galaxy behind one of the clusters allows a strong-lensing mass to be estimated
for this cluster, which is in good agreement with the X-ray measurement.
Optical spectroscopy of this cluster gives a dynamical mass in good agreement
with the other independent mass estimates. The three components of the
RCS2319+00 supercluster are separated from their nearest neighbor by a mere <3
Mpc in the plane of the sky and likely <10 Mpc along the line-of-sight, and we
interpret this structure as the high-redshift antecedent of massive (~10^15
Msun) z~0.5 clusters such as MS0451.5-0305.Comment: ApJ Letters accepted. 5 pages in emulateapj, 3 figure
The role of science in physical natural hazard assessment : report to the UK Government by the Natural Hazard Working Group
Following the tragic Asian tsunami on 26 December 2004, the Prime Minister asked
the Government’s Chief Scientific Adviser, Sir David King, to convene a group of
experts (the Natural Hazard Working Group) to advise on the mechanisms that could
and should be established for the detection and early warning of global physical
natural hazards.
2. The Group was asked to examine physical hazards which have high global or regional
impact and for which an appropriate early warning system could be put in place. It
was also asked to consider the global natural hazard frameworks currently in place
and under development and their effectiveness in using scientific evidence; to
consider whether there is an existing appropriate international body to pull together
the international science community to advise governments on the systems that need
to be put in place, and to advise on research needed to fill current gaps in knowledge.
The Group was asked to make recommendations on whether a new body was
needed, or whether other arrangements would be more effective
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