A DNA-based method for detecting homologous blood doping

Homologous (or allogeneic) blood doping, in which blood is transferred from a donor into a recipient athlete, is the easiest, cheapest, and fastest way to increase red cell mass (hematocrit) and therefore the oxygen-carrying capacity of the blood. Although thought to have been rendered obsolete as a doping strategy by the increased use of rhEPO to increased hematocrits, there is evidence that athletes are still using this potentially dangerous method to improve endurance performance. Current testing for homologous blood doping is based on identification of mixed populations of red blood cells by flow cytometry. This paper proposes that homologous blood doping could also be tested for by high-resolution qPCR-based genotyping and demonstrates that assays could be developed that would detect second populations of cells even if the “donor” blood was depleted of 99 % of the DNA-containing leukocytes. Issues of test specificity and sensitivity are discussed as well as some of the ethical considerations that would have to be addressed if athletes’ genotypes were to be used by the anti-doping authorities to prevent, or detect, the use of prohibited ergogenic practices.     

Weakly coupled bound states of Pauli operators

We consider the two-dimensional Pauli operator perturbed by a weakly coupled, attractive potential. We show that besides the eigenvalues arising from the Aharonov?CCasher zero modes there are two or one (depending on whether the flux of the magnetic field is integer or not) additional eigenvalues for arbitrarily small coupling and we calculate their asymptotics in the weak coupling limit.     

Equidivisible kleene monoids and the Elgot-Mezei theorem

Equidivisible Kleene monoids satisfy the Elgot-Mezei theorem.     

Excited-state processes in first-generation phenyl-cored thiophene dendrimers

First generation dendrimers with three oligothiophene arms (meta-arranged, 3G1-nS) and four arms (ortho- and para-arranged, 4G1-nS) connected to a central phenyl core were investigated spectroscopically in solution. In all dendrimers, on an ultrafast time scale (<10 ps), two "cooling" processes convert the initially generated, "hot" exciton into the geometrically relaxed, "cold" exciton. A decrease in the triplet yield, particularly evident for the 4-arm dendrimers; intersystem crossing rate; and nonradiative triplet decay time with increasing number of bridging thiophene units n all meet with expectations from prior studies on linear oligothiophenes. A relatively fast internal conversion process (>0.6 ns(-1)) is observed in both dendrimer series, possibly due to increased twisting about the phenyl core that reduces the triplet yields considerably with respect to oligothiophenes. An anomalous shifting of the triplet-triplet absorption spectra characterizes the 4G1-nS dendrimers as unique from the 3G1-nS series in terms of the hindrance of torsional motion and confinement of excited states enforced by the arrangement of dendrons.     

New Raman Spectroscopic Data of the Almahata Sitta Meteorite

The archaeological site of Pintia (Padilla de Duero/Peñafiel, Valladolid), considered one of the first cities on the Iberian Peninsula, has yielded very interesting archaeological records regarding the different functional areas that involve the oppidum. Pottery, metal, and bone/skeletal remains are very well preserved, being optimal for analysis and study of the ancient food contained, such as milk-based products, animal fats, beer, and wine. The combination of Raman Microscopy (RM) with other analytical techniques such as Light Microscopy (LM) and Environmental Scanning Electron Microscopy equipped with Energy Dispersive X-ray Spectroscopy (ESEM-EDX) becomes a powerful tool to obtain information on the possible content in the ceramic receptacles from historical-archaeological heritage. It can lead to an interpretation of their specific use or functionality. In this work, a unique sample preparation was used for all techniques, which lead to a very simple procedure and documentation. The degradation and aging of natural fibers and the presence of organic matter with low crystallinity and calcium oxalate–related residuals can be studied by these combined techniques. The archaeological residuals can be separated from modern contamination coming from agriculture processes, surrounding land minerals, or fresh vegetal matter.     

Number of Bound States of Schrödinger Operators with Matrix-Valued Potentials

We give a Cwikel–Lieb–Rozenblum type bound on the number of bound states of Schrödinger operators with matrix-valued potentials using the functional integral method of Lieb. This significantly improves the constant in this inequality obtained earlier by Hundertmark.