Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 38 )

2019 ( 233 )

2018 ( 320 )

2017 ( 297 )

Custom range...

Search Results: 1 - 10 of 297953 matches for " J. Hein "
All listed articles are free for downloading (OA Articles)
Page 1 /297953
Display every page Item
Heavy quarks in non-relativistic lattice QCD
J. Hein
Physics , 1998,
Abstract: I give an overview of phenomenological heavy quark results obtained in NRQCD on the lattice. In particular I discuss the bottomonium and the b-light hadron spectrum. I also review recent results on the decay constants f_B and f_B_s.
Simulations of the electroweak plasma at finite temperature
J. Hein
Physics , 1997,
Abstract: We investigate the SU(2) Higgs model at a Higgs Boson mass of \simeq 34 GeV for temperatures at the electroweak scale. We discuss in detail the critical temperature, the scalar field vacuum expectation value and the latent heat. We also consider for which temperatures the plasma can be regarded as radiation dominated.
Pseudoscalar decay constant in the heavy light systems
J. Hein
Physics , 1998, DOI: 10.1016/S0920-5632(99)85075-0
Abstract: We discuss the size of the higher order terms in the NRQCD expansion of the pseudoscalar decay constant. Power law divergences in the matrix elements contributing to the pseudoscalar decay constant are also investigated.
Sudden cardiac arrest – How can we improve results of resuscitation?
Hein J. Wellens
Applied Cardiopulmonary Pathophysiology , 2012,
Abstract: Death from heart disease has continued to diminish during the last two decades, but still half of those deaths are sudden, often occurring unexpectedly outside hospital, claiming at least 250.000 lives in Europe each year. What can we do to prevent this from happening and how can we successfully resuscitate the victim?When an arrhythmic sudden death occurs outside the hospital, the only chance for survival is recognition of the situation by a witness, the start of cardiac massage and a call to bring a defibrillator and experienced people to the scene as soon as possible. Increasing the number of people trained in resuscitation, and the density of the automatic external defibrillator in the community are important factors to increase the success rate of the resuscitation attempt. However, a real breakthrough requires the development of a device that recognizes cardiac arrest, sounds an alarm, and transmits the location of the victim, thereby shortening the time interval of the different steps in the chain of survival.
Numerical evolution of axisymmetric, isolated systems in General Relativity
J. Frauendiener,Matthias Hein
Physics , 2002, DOI: 10.1103/PhysRevD.66.124004
Abstract: We describe in this article a new code for evolving axisymmetric isolated systems in general relativity. Such systems are described by asymptotically flat space-times which have the property that they admit a conformal extension. We are working directly in the extended `conformal' manifold and solve numerically Friedrich's conformal field equations, which state that Einstein's equations hold in the physical space-time. Because of the compactness of the conformal space-time the entire space-time can be calculated on a finite numerical grid. We describe in detail the numerical scheme, especially the treatment of the axisymmetry and the boundary.
Adsorption of Vapor Phase Mercury on Various Carbons  [PDF]
Jinjing Luo, A. M. Hein, J.Y. Hwang
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2004, DOI: 10.4236/jmmce.2004.31002
Abstract: Unburned carbon was found to be a component of fly ash resulting from incomplete combustion in a pulverized-coal based power plant. Previous investigations found that unburned carbon separated from fly ash exhibited good mercury adsorption property. It would offer an opportunity to substitute activated carbon with low cost unburned carbon for mercury adsorption from power plant emission gases. This study provides a comparison of mercury adsorption by carbon from various sources, including activated carbon and unburned carbon from two different power plants. The experimnts were conducted under various temperatures and mercury concentrations to determine whether good mercury adsorption properties can be obtained from various carbon sources. This study revealed that mercury adsorption depended on the carbon sources and conditions. Activated carbon (F400) demonstrated the best mercury absorbability among the three tested carbons, followed by AEP unburned carbon. Pepco unburned carbon showed very little mercury absorbability. Increasing the temperature generally resulted in the decrease of mercury adsorption. Adsorption rate could be effectively increased with increasing gaseous Hg concentration. Desorption treatment before adsorption test could improve unburned carbon’s adsorption capacity, especially for Pepco carbon.
Genomic Resources and Tools for Gene Function Analysis in Potato
Glenn J. Bryan,Ingo Hein
International Journal of Plant Genomics , 2008, DOI: 10.1155/2008/216513
Abstract: Potato, a highly heterozygous tetraploid, is undergoing an exciting phase of genomics resource development. The potato research community has established extensive genomic resources, such as large expressed sequence tag (EST) data collections, microarrays and other expression profiling platforms, and large-insert genomic libraries. Moreover, potato will now benefit from a global potato physical mapping effort, which is serving as the underlying resource for a full potato genome sequencing project, now well underway. These tools and resources are having a major impact on potato breeding and genetics. The genome sequence will provide an invaluable comparative genomics resource for cross-referencing to the other Solanaceae, notably tomato, whose sequence is also being determined. Most importantly perhaps, a potato genome sequence will pave the way for the functional analysis of the large numbers of potato genes that await discovery. Potato, being easily transformable, is highly amenable to the investigation of gene function by biotechnological approaches. Recent advances in the development of Virus Induced Gene Silencing (VIGS) and related methods will facilitate rapid progress in the analysis of gene function in this important crop.
Multi-party entanglement in graph states
M. Hein,J. Eisert,H. J. Briegel
Physics , 2003, DOI: 10.1103/PhysRevA.69.062311
Abstract: Graph states are multi-particle entangled states that correspond to mathematical graphs, where the vertices of the graph take the role of quantum spin systems and edges represent Ising interactions. They are many-body spin states of distributed quantum systems that play a significant role in quantum error correction, multi-party quantum communication, and quantum computation within the framework of the one-way quantum computer. We characterize and quantify the genuine multi-particle entanglement of such graph states in terms of the Schmidt measure, to which we provide upper and lower bounds in graph theoretical terms. Several examples and classes of graphs will be discussed, where these bounds coincide. These examples include trees, cluster states of different dimension, graphs that occur in quantum error correction, such as the concatenated [7,1,3]-CSS code, and a graph associated with the quantum Fourier transform in the one-way computer. We also present general transformation rules for graphs when local Pauli measurements are applied, and give criteria for the equivalence of two graphs up to local unitary transformations, employing the stabilizer formalism. For graphs of up to seven vertices we provide complete characterization modulo local unitary transformations and graph isomorphies.
Tree measures and the number of segregating sites in time-structured population samples
Roald Forsberg, Alexei J Drummond, Jotun Hein
BMC Genetics , 2005, DOI: 10.1186/1471-2156-6-35
Abstract: We use results from the coalescent process to derive properties of time-structured samples. In the first section we extend existing results to attain measures on coalescent trees relating time-structured samples. These include the expected time to a most recent common ancestor, the expected total branch length and the expected length of branches subtending only ancient individuals. The effect of different sampling schemes on the latter measure is studied. In the second section we study the special case where the full sample consists of a group of contemporary extant samples and a group of contemporary ancient samples. As regards this case, we present results and applications concerning the probability distribution of the number of segregating sites where a mutation is unique to the ancient individuals and the number of segregating sites where a mutation is shared between ancient and extant individuals.The methodology and results presented here is of use to the design and interpretation of ancient DNA experiments. Furthermore, the results may be useful in further development of statistical tests of e.g. population dynamics and selection, which include temporal information.Genetic samples obtained over several points in time are a valuable source of information in population genetics because they provide several correlated observations of the underlying evolutionary processes.These time-structured samples can be separated into two qualitatively different groups. Firstly, samples may be taken over such a short evolutionary time that the occurrence of mutations between sampling points can be ignored. Samples of this type have a long standing history in the study of the process of drift and selection via observations of allele frequencies (see e.g. [1]). Secondly, time-structured samples may be obtained over intervals of evolutionary time that are long enough for mutation to become a relevant force in shaping the diversity between samples from different time points. To r
Asymptotically conical Calabi-Yau metrics on quasi-projective varieties
Ronan J. Conlon,Hans-Joachim Hein
Mathematics , 2013,
Abstract: Let X be a compact Kahler orbifold without \C-codimension-1 singularities. Let D be a suborbifold divisor in X such that D \supset Sing(X) and -pK_X = q[D] for some p, q \in \N with q > p. Assume that D is Fano. We prove the following two main results. (1) If D is Kahler-Einstein, then, applying results from our previous paper, we show that each Kahler class on X\D contains a unique asymptotically conical Ricci-flat Kahler metric, converging to its tangent cone at infinity at a rate of O(r^{-1-\epsilon}) if X is smooth. This provides a definitive version of a theorem of Tian and Yau. (2) We introduce new methods to prove an analogous statement (with rate O(r^{-0.0128})) when X = Bl_{p}P^3 and D = Bl_{p_1,p_2}P^2 is the strict transform of a smooth quadric through p in P^3. Here D is no longer Kahler-Einstein, but the normal S^1-bundle to D in X admits an irregular Sasaki-Einstein structure which is compatible with its canonical CR structure. This provides the first example of an affine Calabi-Yau manifold of Euclidean volume growth with irregular tangent cone at infinity.
Page 1 /297953
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.