The GSI anomaly

Recently, an experiment at GSI Darmstadt has observed oscillating decay rates of heavy ions. Several controversial attempts have been made to explain this effect in terms of neutrino mixing. We briefly describe the experimental results, give an overview of the literature, and show that the effect cannot be due to neutrino mixing. If the effect survives, it could, however, be explained by hypothetical internal excitations of the mother ions (~ 10^(-15) eV).Comment: Contribution to the Proceedings of Neutrino 2008, based on a talk by M. Lindner and on a poster by the author

Seasonal changes in serum testosterone, 11-ketotestosterone, and 1713-estradiol levels in the brown bullhead, Ictalurus nebuIosus Lesueur

The seasonal changes in gonadosomatic index (GSI) and strum testosterone, I I-ketotestosterone, and 17&estmdiol levels were measured in adult feral brown bullheads, Ictalurus nebulosus Lzsueur. The maximum GSI of both male and femalz brown bullheads was consjderably lower than that of most other teleostean species investigated. lo males, the GSI began to increase in April concomitant with an increase in water temperature from 3 to 6°C. The maximum GSI levels were evident throu_ghout May and June (during the prespawning and spawning periods). Peaks of serum testosterone and serum 11-ketotesrosterone leveb were evident in mid-April and late May to June, and in mid-April and mid-May, respxtively. In females here was a rapid increase in GSI during May, when the ambient water temperamre reached 16°C. The peak GSI was evident in mid- to late-May and had declined by early June. Peak serum testosterone and I 1-ketotestosterone levels were evident .in mid-April and again in late May. wbereas peak 17P-estradiol levels were fou.nd in mid-May and mid-June. The peak serum teswsterone levels in females were 4.5-fold higher than in the males, whereas che I I-ketotestosterone levels were similar in males and females

Enhanced controlling of the SLS Process during a build

Current commercial Rapid Prototyping (RP) systems like Stereolithography (3D Systems Corporation) and Selective Laser Sintering (DTM Corporation) use galvanometers from General Scanning Inc. (GSI) for the positioning of the laser beam. The GSI scanners are delivered as a ''black box". Operating Consoles which are usually Personal Computers (PC) have very few feedback from the performance of the GSI scanners. Therefore, the PC spends 9000 or more of its time waiting for the GSI scanners to be over with the building of the current layer before sending the information regarding the next layer. Also, very little process control can be performed during the scanning of a layer using the GSI scanners. This kind of setup prevents any dynamic controlling of the process that could prevent building errors like burning, warping etc. At Clemson University, our team has developed both hardware and software components that allows a dynamic control of the building process. New features like scanning one vector with laser power as a function of position and/or time are now possible. Both hardware and software issues will be presented.Mechanical Engineerin

Expression and trans-specific polymorphism of self-incompatibility RNases in Coffea (Rubiaceae)

Self-incompatibility (SI) is widespread in the angiosperms, but identifying the biochemical components of SI mechanisms has proven to be difficult in most lineages. Coffea (coffee; Rubiaceae) is a genus of old-world tropical understory trees in which the vast majority of diploid species utilize a mechanism of gametophytic self-incompatibility (GSI). The S-RNase GSI system was one of the first SI mechanisms to be biochemically characterized, and likely represents the ancestral Eudicot condition as evidenced by its functional characterization in both asterid (Solanaceae, Plantaginaceae) and rosid (Rosaceae) lineages. The S-RNase GSI mechanism employs the activity of class III RNase T2 proteins to terminate the growth of "self" pollen tubes. Here, we investigate the mechanism of Coffea GSI and specifically examine the potential for homology to S-RNase GSI by sequencing class III RNase T2 genes in populations of 14 African and Madagascan Coffea species and the closely related self-compatible species Psilanthus ebracteolatus. Phylogenetic analyses of these sequences aligned to a diverse sample of plant RNase T2 genes show that the Coffea genome contains at least three class III RNase T2 genes. Patterns of tissue-specific gene expression identify one of these RNase T2 genes as the putative Coffea S-RNase gene. We show that populations of SI Coffea are remarkably polymorphic for putative S-RNase alleles, and exhibit a persistent pattern of trans-specific polymorphism characteristic of all S-RNase genes previously isolated from GSI Eudicot lineages. We thus conclude that Coffea GSI is most likely homologous to the classic Eudicot S-RNase system, which was retained since the divergence of the Rubiaceae lineage from an ancient SI Eudicot ancestor, nearly 90 million years ago.United States National Science Foundation [0849186]; Society of Systematic Biologists; American Society of Plant Taxonomists; Duke University Graduate Schoolinfo:eu-repo/semantics/publishedVersio

SPIN Physics at GSI

Polarized antiprotons produced by spin filtering with an internal polarized gas target provide access to a wealth of single-- and double--spin observables, thereby opening a window to physics uniquely accessible with the HESR at FAIR. This includes a first measurement of the transversity distribution of the valence quarks in the proton, a test of the predicted opposite sign of the Sivers--function, related to the quark distribution inside a transversely polarized nucleon, in Drell--Yan (DY) as compared to semi--inclusive DIS, and a first measurement of the moduli and the relative phase of the time--like electric and magnetic form factors G_{E,M} of the proton. In polarized and unpolarized proton--antiproton elastic scattering open questions like the contribution from the odd charge--symmetry Landshoff--mechanism at large |t| and spin--effects in the extraction of the forward scattering amplitude at low |t| can be addressed.Comment: 10 pages, 3 figures. Contribution to the Proceedings of the 16th International Spin Physics Symposium, Spin 2004, October 10-16, 2004, Trieste, Italy. This replacement takes into account a request of the conference organizers that for invited talks only a single author is allowed. Also upon request of the conference organizers, a footnote (c) was added, which explains that some of the material presented was developed only after the oral presentation at the conferenc

The GSI oscillation mystery

In this talk, a short discussion of the GSI anomaly is given. We discuss the physics involved using a comparison with pion decay, and explain why the observed oscillations cannot be caused by standard neutrino mixing.Comment: 3 pages, 1 figure; part of the proceedings of the "International School of Nuclear Physics, 31st Course, 'Neutrinos in Cosmology, in Astro-, Particle- and Nuclear Physics' " in Erice, Italy, 16 - 24 September 200

Strangeness Equilibration at GSI Energies

We develop the notion of "broad-band equilibration" in heavy-ion processes involving dense medium. Given density-dependent \Km-masses we show that the equilibration at GSI energies claimed to hold in previous treatments down to $\sim \rho_0/4$, can be replaced by a broad-band equilibration in which the \Km-meson and hyperons are produced in an essentially constant ratio independent of density. There are experimental indications that this also holds for AGS energies. We then proceed to argue that {\it both} $K^+$ and $K^-$ must get lighter in dense medium at some density $\rho >\rho_0$ due to the decoupling of the vector mesons. As a consequence, kaon condensation in compact stars could take place {\it before} chiral restoration since the sum of bare quark masses in the kaon should lie below $\mu_e$. Another consequence of the decoupling vector interactions is that the quasi-particle picture involving (quasi)quarks, presumably ineffective at low densities, becomes more appropriate at higher densities as chiral restoration is approached.Comment: 16 pages, latex with 2 eps figures. Abstract rewritten and references update