37 research outputs found
The new p-process database of KADoNiS
The KADoNiS (Karlsruhe Astrophysical Database of Nucleosynthesis in Stars) project is an online
database (www.kadonis.org) for cross sections relevant to the s-process and the p-process.
The first version was an updated sequel to the previous Bao et al. [1] compilations from 1987
and 2000 for (n; g) cross sections relevant to Big Bang and s-process nucleosynthesis. The first
update, KADoNiS v0.2, was published in 2006 [2]. It contained mainly Maxwellian averaged
(n; g) cross sections relevant to the s-process, and some experimental charged particle induced
reaction relevant to the p-process. After that a second update was presented in 2009 [3].
Recently, we started to collect and review all existing experimental data relevant for p-process
nucleosynthesis and to provide a user-friendly database based on the KADoNiS framework. The
p-process part of the KADoNiS database is currently being extended and will include all available
experimental data from (p; g), (p;n), (p;a), (a,g), (a;n) and (a; p) reactions in or close to the
respective Gamow window
Exploring the Extracellular Matrix to Create Biomaterials
The extracellular matrix (ECM) represents the framework of tissues and organs and is involved in cell differentiation and function. The study of ECM is challenging and required a combination of identification and imaging techniques to give a valuable scheme of its composition, organization, and finally function. The study of ECM enables to culture cells ex vivo, but cultures are restricted to two-dimensional surfaces, whereas in the meantime, material sciences were developing devices able to bring cell culture in a three-dimensional (3D) environment. This chapter presents basic techniques to investigate extracellular matrices composition and organization. Basic knowledge on ECM composition and organization should inspire material scientists to propose more biologically relevant materials. In a second time, we present strategies available to create ex vivo models of ECM and a series of examples of 3D materials that were engineered to investigate cell adhesion, phenotype, and differentiation in a biologically relevant microenvironment. The production of a gold-standard material is possible for a specific biological question, and it might be developed from an intelligible dialogue between material scientists, that bring engineering strategies, and cell biologists who implement the material design to meet the biological process that has to be investigated ex vivo
A novel measurement approach and evidence for multi-system physiological dysregulation during aging
Abstract: Previous studies have identified many biomarkers that are associated with aging and related
outcomes, but the relevance of these markers for underlying processes and their relationship
to hypothesized systemic dysregulation is not clear. We address this gap by presenting a novel
method for measuring dysregulation via the joint distribution of multiple biomarkers and
assessing associations of dysregulation with age and mortality. Using longitudinal data from
the Womenâs Health and Aging Study, we selected a 14-marker subset from 63 blood
measures: those that diverged from the baseline population mean with age. For the 14 markers
and all combinatorial sub-subsets we calculated a multivariate distance called the
Mahalanobis distance (MHBD)2 for all observations, indicating how âstrangeâ each
individualâs biomarker profile was relative to the baseline population mean. In most models,
MHBD correlated positively with age, MHBD increased within individuals over time, and
higher MHBD predicted higher risk of subsequent mortality. Predictive power increased as
more variables were incorporated into the calculation of MHBD. Biomarkers from multiple
systems were implicated. These results support hypotheses of simultaneous dysregulation in
multiple systems and confirm the need for longitudinal, multivariate approaches to
understanding biomarkers in aging
Immunosenescence and Cytomegalovirus: where do we stand after a decade?
AbstractSince Looney at al. published their seminal paper a decade ago it has become clear that many of the differences in T cell immunological parameters observed between young and old people are related to the age-associated increasing prevalence of infection with the persistent beta-herpesvirus HHV-5 (Cytomegalovirus). Ten years later, studies suggest that hallmark age-associated changes in peripheral blood T cell subset distribution may not occur at all in people who are not infected with this virus. Whether the observed changes are actually caused by CMV is an open question, but very similar, rapid changes observed in uninfected patients receiving CMV-infected kidney grafts are consistent with a causative role. This meeting intensively discussed these and other questions related to the impact of CMV on human immune status and its relevance for immune function in later life.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
Measurements of proton-induced reactions on ruthenium-96 in the ESR at GSI
8th International Conference on Nuclear Physics at Storage Rings Stori11, October 9-14, 2011 Laboratori Nazionale di Frascati, Italy.
Storage rings offer the possibility of measuring proton- and alpha-induced reactions in inverse kinematics. The combination of this approachwith a radioactive beamfacility allows, in principle, the determination of the respective cross sections for radioactive isotopes. Such data are highly desired for a better understanding of astrophysical nucleosynthesis processes like the p-process. A pioneering experiment has been performed at the Experimental Storage Ring (ESR) at GSI using a stable 96Ru beam at 9-11 AMeV and a hydrogen target. Monte-Carlo simulations of the experiment were made using the Geant4 code. In these simulations, the experimental setup is described in detail and all reaction channels can be investigated. Based on the Geant4 simulations, a prediction of the shape of different spectral components can be performed. A comparison of simulated predictions with the experimental results shows a good agreement and allows the extraction of the cross section