4,919 research outputs found
New Physics at the International Facility for Antiproton and Ion Research (FAIR) Next to GSI
The project of the international Facility for Antiproton and Ion Research
(FAIR), co-located to the GSI facility in Darmstadt, has been officially
started on November 7, 2007. The current plans of the facility and the planned
research program will be described. An investment of about 1 billion euro will
permit new physics programs in the areas of low and medium energy antiproton
research, heavy ion physics complementary to LHC, as well as in nuclear
structure and astrophysics. The facility will comprise about a dozen
accelerators and storage rings, which will enable simultaneous operations of up
to four different beams.Comment: 7 pages, 1 figure. Invited Talk presented at the "Fourth
International Conference on Fission and Properties of Neutron-Rich nuclei",
held at Sanibel Island, Florida, November 11-17, 200
Metastasis: imaging shows the way
Metastasis, the life threatening aspect of cancer, is a systemic disease process. Considerable progress has been made in recent years regarding how tumor cells circulating in the blood and lymphatic systems interact with and extravasate into secondary sites, and what determines whether these disseminated tumors cells survive, remain dormant or go on to form macrometastases. New insights into the routes that tumor cells take once leaving the primary tumor have emerged. Novel concepts regarding early seeding of metastases coupled to parallel progression, self-seeding of primary tumors by circulating tumor cells, and the induction of pre-metastatic niches in distant organs by primary tumors have come to the fore. In our presentations we will review these and other paradigm shifts that have taken place over recent years, placing a particular focus on how the use of intravital and other imaging techniques have played a major role in these developments
Restriction on the energy and luminosity of e+e- storage rings due to beamstrahlung
The role of beamstrahlung in high-energy e+e- storage-ring colliders (SRCs)
is examined. Particle loss due to the emission of single energetic
beamstrahlung photons is shown to impose a fundamental limit on SRC
luminosities at energies 2E_0 >~ 140 GeV for head-on collisions and 2E_0 >~ 40
GeV for crab-waist collisions. With beamstrahlung taken into account, we
explore the viability of SRCs in the E_0=240-500 GeV range, which is of
interest in the precision study of the Higgs boson. At 2E_0=240 GeV, SRCs are
found to be competitive with linear colliders; however, at 2E_0=400-500 GeV,
the attainable SRC luminosity would be a factor 15-25 smaller than desired.Comment: Latex, 5 pages. v2 differs only by minor changes is abstract and
introduction, one reference is added. v3 corresponds to the paper published
in PR
Restoration of peatlands and greenhouse gas balances
In this chapter the impact of peatland restoration on greenhouse gas fluxes is discussed based on a literature review. Casestudies are presented covering different peatland types, different regions and different starting conditions
Using Agency Theory as an Organizing Principle for Pension Accounting
Gerald H. Lander is Professor of Accounting, College of Business at the University of South Florida. Alan Reinstein is Professor of Accounting, School of Business Administration at Wayne State University. Augustin K. Fosu is an Associate Professor of Economics, School of Business Administration at Oakland University
Drilling of shallow marine sulfide-sulfate mineralisation in south-eastern Tyrrhenian Sea, Italy; Seafloor sulfides, Tyrrhenian Sea, highsulfidation; hydrothermal systems, Palinuro
Semi-massive to massive sulfides with abundant late native sulfur were drilled in a shallowwater hydrothermal system in an island arc volcanic setting at the Palinuro volcanic complex in the Tyrrhenian Sea, Italy. Overall, 12.7 m of sulfide mineralisation were drilled in a sediment-filled
depression at a water depth of 630 - 650 m using the
lander-type Rockdrill I drill rig of the British Geological
Survey. Polymetallic (Zn, Pb, Sb, As, Ag) sulfides
overlie massive pyrite. The massive sulfide mineralisation contains a number of atypical minerals, including enargite-famatinite, tennantite-tetrahedrite, stibnite, bismuthinite, and Pb-,Sb-, and Ag-sulfosalts, that do not commonly occur in mid-ocean ridge massive sulfides. Analogous to subaerial epithermal deposits, the occurrence of these minerals and the presence of abundant native sulfur suggest an intermediate to high sulfidation and/or high oxididation state of the hydrothermal fluids in contrast to the near-neutral and reducing fluids from which base metal-rich massive sulfides along mid-ocean ridges typically form. Oxidised conditions during sulfide deposition are likely related to the presence of magmatic volatiles in the mineralising fluids that were derived from a degassing magma chamber below the Palinuro volcanic complex
Generalized Additive Models for Gigadata:Modeling the U.K. Black Smoke Network Daily Data
<p>We develop scalable methods for fitting penalized regression spline based generalized additive models with of the order of 10<sup>4</sup> coefficients to up to 10<sup>8</sup> data. Computational feasibility rests on: (i) a new iteration scheme for estimation of model coefficients and smoothing parameters, avoiding poorly scaling matrix operations; (ii) parallelization of the iteration’s pivoted block Cholesky and basic matrix operations; (iii) the marginal discretization of model covariates to reduce memory footprint, with efficient scalable methods for computing required crossproducts directly from the discrete representation. Marginal discretization enables much finer discretization than joint discretization would permit. We were motivated by the need to model four decades worth of daily particulate data from the U.K. Black Smoke and Sulphur Dioxide Monitoring Network. Although reduced in size recently, over 2000 stations have at some time been part of the network, resulting in some 10 million measurements. Modeling at a daily scale is desirable for accurate trend estimation and mapping, and to provide daily exposure estimates for epidemiological cohort studies. Because of the dataset size, previous work has focused on modeling time or space averaged pollution levels, but this is unsatisfactory from a health perspective, since it is often acute exposure locally and on the time scale of days that is of most importance in driving adverse health outcomes. If computed by conventional means our black smoke model would require a half terabyte of storage just for the model matrix, whereas we are able to compute with it on a desktop workstation. The best previously available reduced memory footprint method would have required three orders of magnitude more computing time than our new method. Supplementary materials for this article are available online.</p
Impact of secondary hard substrate on the distribution and abundance of Aurelia aurita in the western Baltic Sea
Highlights:
• Impacts of wind farms on the occurrence of the moon jelly Aureliaaurita.
• Artificial hard substrate has the potential to increase the abundance of A.aurita.
• In the given example the abundance of A. aurita increases about 20%.
• Distribution patterns indicate cross-border impacts on various sectors.
This study assessed the impact of secondary hard substrate, as being introduced into marine ecosystems by the establishment of wind farm pillars, on the occurrence and distribution of the moon jelly Aurelia aurita in the southwestern Baltic Sea. A two-year data sampling was conducted with removable settlement plates to assess the distribution and population development of the scyphozoan polyps. The data collected from these samples were used to set up a model with Lagrangian particle technique. The results confirm that anthropogenic created hard substrate (e.g. offshore wind farms) has the potential to increase the abundance of the A. aurita population. The distribution of wind farm borne jellyfish along Danish, German and Polish coasts indicates conflicts with further sectors, mainly energy and tourism
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