1,194 research outputs found

    Spin-one color superconductivity in compact stars?- an analysis within NJL-type models

    Full text link
    We present results of a microscopic calculation using NJL-type model of possible spin-one pairings in two flavor quark matter for applications in compact star phenomenology. We focus on the color-spin locking phase (CSL) in which all quarks pair in a symmetric way, in which color and spin states are locked. The CSL condensate is particularly interesting for compact star applications since it is flavor symmetric and could easily satisfy charge neutrality. Moreover, the fact that in this phase all quarks are gapped might help to suppress the direct Urca process, consistent with cooling models. The order of magnitude of these small gaps (~1 MeV) will not influence the EoS, but their also small critical temperatures (T_c ~800 keV) could be relevant in the late stages neutron star evolution, when the temperature falls below this value and a CSL quark core could form.Comment: 7 pages, 7 figures, revised version, accepted for the Conference Proceedings of "Isolated Neutron Stars: from the Interior to the Surface", London, 24-28. April 200

    A variational approach to strongly damped wave equations

    Full text link
    We discuss a Hilbert space method that allows to prove analytical well-posedness of a class of linear strongly damped wave equations. The main technical tool is a perturbation lemma for sesquilinear forms, which seems to be new. In most common linear cases we can furthermore apply a recent result due to Crouzeix--Haase, thus extending several known results and obtaining optimal analyticity angle.Comment: This is an extended version of an article appeared in \emph{Functional Analysis and Evolution Equations -- The G\"unter Lumer Volume}, edited by H. Amann et al., Birkh\"auser, Basel, 2008. In the latest submission to arXiv only some typos have been fixe

    Characterization of Procoagulant COAT Platelets in Patients with Glanzmann Thrombasthenia.

    Get PDF
    Patients affected by the rare Glanzmann thrombasthenia (GT) suffer from defective or low levels of the platelet-associated glycoprotein (GP) IIb/IIIa, which acts as a fibrinogen receptor, and have therefore an impaired ability to aggregate platelets. Because the procoagulant activity is a dichotomous facet of platelet activation, diverging from the aggregation endpoint, we were interested in characterizing the ability to generate procoagulant platelets in GT patients. Therefore, we investigated, by flow cytometry analysis, platelet functions in three GT patients as well as their ability to generate procoagulant collagen-and-thrombin (COAT) platelets upon combined activation with convulxin-plus-thrombin. In addition, we further characterized intracellular ion fluxes during the procoagulant response, using specific probes to monitor by flow cytometry kinetics of cytosolic calcium, sodium, and potassium ion fluxes. GT patients generated higher percentages of procoagulant COAT platelets compared to healthy donors. Moreover, they were able to mobilize higher levels of cytosolic calcium following convulxin-plus-thrombin activation, which is congruent with the greater procoagulant activity. Further investigations will dissect the role of GPIIb/IIIa outside-in signalling possibly implicated in the regulation of platelet procoagulant activity

    The Delphi technique in ecology and biological conservation: Applications and guidelines

    Get PDF
    1. Many areas of science, including conservation and environmental management, regularly require engaging stakeholders or experts to produce consensus or technical inputs. The Delphi technique is an iterative and anonymous participatory method used for gathering and evaluating such expert-based knowledge. 2. We outline the methodology of the Delphi technique and provide a taxonomy of its main variants. In addition, we refine the technique by providing suggestions to address common limitations (e.g. time consumption, attrition rate) in order tomake the method more suitable for application in ecology and conservation. 3. A comprehensive search for studies that have applied the Delphi technique in conservation and environmental management resulted in 36 papers. The Delphi technique has been applied to a range of issues, including developing decision support systems and predicting ecological impacts of climate change. 4. The papers reviewed suggest that the Delphi technique is an efficient, inclusive, systematic and structured approach that can be used to address complex issues. A major strength compared to other group-based techniques is the reduced influence of social pressures among respondents. 5. The Delphi technique is relatively little used and seems undervalued. Given its wide range of possible applications, it could be applied more widely in evaluating evidence and providing expert judgments.The authors would like to thank Pinaki Bhattacharya, Maria Voigt, Francisco Benitez-Capistros and the three anonymous reviewers for their significant contributions in improving the earlier manuscript. WJS is funded by Arcadia. NM and JH were funded by the Belgian National Science Foundation (FNRS), MIS ID 1765914 project. NM was also funded by the Fondation Weiner Anspach (FWA) postdoctoral fellowship.This is the author accepted manuscript. The final version is available from Wiley at http://dx.doi.org/10.1111/2041-210X.1238

    Environmental studies data base development and data synthesis activities of the US Subseabed Disposal Program

    Get PDF
    The US Subseabed Disposal Program is assessing the scientific feasibility of subseabed emplacement of high-level nuclear wastes. Studies of disposal methods and of the barriers to radionuclide migration (canister, waste form and sediment) suggest that environmental information will be needed to address the impact of accidental release of radionuclides in the deep sea. Biological, physical, and geochemical data are being collected from field and laboratory studies as well as from literature searches. These data are being analyzed using a multicompartmental radionuclide transport model and appropriate physical oceanographic models. The data integrated into this framework will help answer two questions: what are the environmental effects of radionuclides which may be released in the deep sea, and what are the effects of such a release upon man

    Aedes albopictus diversity and relationships in south-western Europe and Brazil by rDNA/mtDNA and phenotypic analyses: ITS-2, a useful marker for spread studies

    Get PDF
    Background: Aedes albopictus is a very invasive mosquito, which has recently colonized tropical and temperate regions worldwide. Of concern is its role in the spread of emerging or re-emerging mosquito-borne diseases. Ae. albopictus from south-western Europe and Brazil were studied to infer genetic and phenetic diversity at intra-individual, intra-population and inter-population levels, and to analyse its spread. Methods: Genotyping was made by rDNA 5.8S-ITS-2 and mtDNA cox1 sequencing to assess haplotype and nucleotide diversity, genetic distances and phylogenetic networks. Male and female phenotyping included combined landmark-and outlined-based geometric morphometrics of wing size and shape. Results: Specimens from seven populations from Spain, France and Brazil provided 12 cox1 and 162 5.8S-ITS-2 haplotypes, with great genetic variability difference between both markers (0.9% vs 31.2%). Five cox1 haplotypes were shared with other countries, mainly Italy, USA and China, but none was shared between Europe and Brazil. The 5.8S-ITS-2 showed 2–7 intra-individual (mean 4.7) and 16–34 intra-/inter-population haplotypes (24.7), including haplotypes shared between Spain, France and Brazil. A 4.3% of ITS-2 haplotypes were shared, mainly with Italy, USA and Thailand, evidencing worldwide spread and introductions from areas where recent outbreaks of Ae. albopictus-transmitted pathogens occurred. Wing size showed sex differences. Wing shape distinguished between Brazilian and European specimens. Both genetic and morphometric markers showed differences between insular Spain and continental Spain, France and Brazil. Conclusions: ITS-2 proves to be a useful marker to assess Ae. albopictus spread, providing pronouncedly more information than cox1, including intra-individual, intra-population and inter-population levels, furnishing a complete overview of the evolutionary exchanges followed by this mosquito. Wing morphometry proves to be a useful phenotyping marker, allowing to distinguish different populations at the level of both male and female specimens. Results indicate the need for periodic surveillance monitorings to verify that no Ae. albopictus with high virus transmission capacity is introduced into Europe. Graphic Abstract: [Figure not available: see fulltext.] © 2021, The Author(s)

    Global QCD Analysis and the CTEQ Parton Distributions

    Get PDF
    The CTEQ program for the determination of parton distributions through a global QCD analysis of data for various hard scattering processes is fully described. A new set of distributions, CTEQ3, incorporating several new types of data is reported and compared to the two previous sets of CTEQ distributions. Comparison with current data is discussed in some detail. The remaining uncertainties in the parton distributions and methods to further reduce them are assessed. Comparisons with the results of other global analyses are also presented.Comment: (Change in Latex style only: 2up style removed since many don't have it.) 35 pages, 23 figures separately submitted as uuencoded compressed ps-file; Michigan State Report # MSU-HEP/41024 and CTEQ 40
    corecore