121 research outputs found
Winter Mass Mortality of Animals in Texas Bays
The Texas coast experienced three unusually cold weather periods in the 1980\u27s, one in 1983 and two in 1989, that caused massive fish kills. Identification of organisms killed and estimation of the number of estuarine fishes and invertebrates killed was accomplished through a systematic standardized approach utilizing airplanes, ground qualitative observations and quantitative counts, and trawling. Of 159 species identified, 103 were fishes, 45 were invertebrates, and 11 were vertebrates other than fishes. About 14 million fishes were killed in December 1983, 11 million in February 1989 and 6 million in December 1989; number of invertebrates killed ranged from 13,000 in February 1989 to 1,000,000 in 1983. These assessments are the largest in area and most comprehensive to be documented in the literature with known levels of precision. Methodology used provides reasonably precise estimates which managers can use to assess extensive widespread kills and subsequent impacts on affected populations. It is recommended that managers consider reducing fishing mortality on the remaining economically important populations after extensive kills to speed recovery of those populations
When LEP and Tevatron combined with WMAP and XENON100 shed light on the nature of Dark Matter
Recently, several astrophysical data or would-be signals has been observed in
different dark-matter oriented experiments. In each case, one could fit the
data at the price of specific nature of the coupling between the Standard Model
(SM) particles and a light Dark Matter candidate: hadrophobic (INTEGRAL,
PAMELA) or leptophobic (WMAP Haze, dijet anomalies of CDF, FERMI Galactic
Center observation). In this work, we show that when one takes into account the
more recent LEP and Tevatron analysis, a light thermal fermionic Dark Matte
(\lesssim 10 GeV) that couples to electrons is mainly ruled out if one combines
the analysis with WMAP constraints. We also study the special case of scalar
dark matter, using a mono-photon events simulation to constrain the coupling of
dark matter to electron.Comment: 8 pages, 6 figure
Description of the inelastic collision of two solitary waves for the BBM equation
We prove that the collision of two solitary waves of the BBM equation is
inelastic but almost elastic in the case where one solitary wave is small in
the energy space. We show precise estimates of the nonzero residue due to the
collision. Moreover, we give a precise description of the collision phenomenon
(change of size of the solitary waves).Comment: submitted for publication. Corrected typo in Theorem 1.
Complementarity of Galactic radio and collider data in constraining WIMP dark matter models
In this work we confront dark matter models to constraints that may be
derived from radio synchrotron radiation from the Galaxy, taking into account
the astrophysical uncertainties and we compare these to bounds set by
accelerator and complementary indirect dark matter searches. Specifically we
apply our analysis to three popular particle physics models. First, a generic
effective operator approach, in which case we set bounds on the corresponding
mass scale, and then, two specific UV completions, the Z' and Higgs portals. We
show that for many candidates, the radio synchrotron limits are competitive
with the other searches, and could even give the strongest constraints (as of
today) with some reasonable assumptions regarding the astrophysical
uncertainties.Comment: 22 pages, 12 figure
Numerical simulations of the Warm-Hot Intergalactic Medium
In this paper we review the current predictions of numerical simulations for
the origin and observability of the warm hot intergalactic medium (WHIM), the
diffuse gas that contains up to 50 per cent of the baryons at z~0. During
structure formation, gravitational accretion shocks emerging from collapsing
regions gradually heat the intergalactic medium (IGM) to temperatures in the
range T~10^5-10^7 K. The WHIM is predicted to radiate most of its energy in the
ultraviolet (UV) and X-ray bands and to contribute a significant fraction of
the soft X-ray background emission. While O VI and C IV absorption systems
arising in the cooler fraction of the WHIM with T~10^5-10^5.5 K are seen in
FUSE and HST observations, models agree that current X-ray telescopes such as
Chandra and XMM-Newton do not have enough sensitivity to detect the hotter
WHIM. However, future missions such as Constellation-X and XEUS might be able
to detect both emission lines and absorption systems from highly ionised atoms
such as O VII, O VIII and Fe XVII.Comment: 18 pages, 5 figures, accepted for publication in Space Science
Reviews, special issue "Clusters of galaxies: beyond the thermal view",
Editor J.S. Kaastra, Chapter 14; work done by an international team at the
International Space Science Institute (ISSI), Bern, organised by J.S.
Kaastra, A.M. Bykov, S. Schindler & J.A.M. Bleeke
Clustering Algorithms: Their Application to Gene Expression Data
Gene expression data hide vital information required to understand the biological process that takes place in a particular organism in relation to its environment. Deciphering the hidden patterns in gene expression data proffers a prodigious preference to strengthen the understanding of functional genomics. The complexity of biological networks and the volume of genes present increase the challenges of comprehending and interpretation of the resulting mass of data, which consists of millions of measurements; these data also inhibit vagueness, imprecision, and noise. Therefore, the use of clustering techniques is a first step toward addressing these challenges, which is essential in the data mining process to reveal natural structures and iden-tify interesting patterns in the underlying data. The clustering of gene expression data has been proven to be useful in making known the natural structure inherent in gene expression data, understanding gene functions, cellular processes, and subtypes of cells, mining useful information from noisy data, and understanding gene regulation. The other benefit of clustering gene expression data is the identification of homology, which is very important in vaccine design. This review examines the various clustering algorithms applicable to the gene expression data in order to discover and provide useful knowledge of the appropriate clustering technique that will guarantee stability and high degree of accuracy in its analysis procedure
How can diverse national food and land-use priorities be reconciled with global sustainability targets? Lessons from the FABLE initiative
There is an urgent need for countries to transition their national food and land-use systems toward food and nutritional security, climate stability, and environmental integrity. How can countries satisfy their demands while jointly delivering the required transformative change to achieve global sustainability targets? Here, we present a collaborative approach developed with the FABLE—Food, Agriculture, Biodiversity, Land, and Energy—Consortium to reconcile both global and national elements for developing national food and land-use system pathways. This approach includes three key features: (1) global targets, (2) country-driven multi-objective pathways, and (3) multiple iterations of pathway refinement informed by both national and international impacts. This approach strengthens policy coherence and highlights where greater national and international ambition is needed to achieve global goals (e.g., the SDGs). We discuss how this could be used to support future climate and biodiversity negotiations and what further developments would be needed
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