Voluntary wheel running reverses the decrease in subventricular zone neurogenesis caused by corticosterone

Adult neurogenesis within the dentate gyrus of the hippocampus can be increased by voluntary exercise but is suppressed under stress, such as with corticosterone (CORT). However, the effects of exercise and corticosterone on the cell proliferation of the other traditional neurogenic site, the subventricular zone (SVZ) have been reported with controversial results. In addition, the co-treatment effects of voluntary exercise and corticosterone have not been investigated. This study aims to determine whether corticosterone can suppress cell proliferation in the SVZ, and whether this can be reversed by voluntary exercise. In the present study, the effect of chronic (4 weeks) corticosterone treatment and wheel running simultaneously on the SVZ cell proliferation of adult Sprague-Dawley rats was examined. The results showed that cell proliferation indicated by bromodeoxyuridine (BrdU) was increased by voluntary wheel running whereas it was decreased by corticosterone treatment within the SVZ of the rats without running. For the rats with both corticosterone treatment and wheel running, it was found that the number of BrdU-labeled cells was approximately at the same level as the vehicle control group. Furthermore, these proliferating cells expressed doublecortin (DCX), a migrating neuroblast marker. Wheel running increased the percentage of BrdU-labeled cells expressing DCX in the SVZ whereas corticosterone treatment decreased this percentage. Thus, chronic injection of corticosterone can decrease the number of proliferating cells while wheel running can reverse the decrease in cell proliferation within the SVZ to normal levels. In addition, corticosterone can suppress the cell differentiation within the SVZ and this was alleviated by wheel running as indicated by the double-labeling of BrdU and DCX.published_or_final_versio

Load-Balancing for Parallel Delaunay Triangulations

Computing the Delaunay triangulation (DT) of a given point set in $\mathbb{R}^D$ is one of the fundamental operations in computational geometry. Recently, Funke and Sanders (2017) presented a divide-and-conquer DT algorithm that merges two partial triangulations by re-triangulating a small subset of their vertices - the border vertices - and combining the three triangulations efficiently via parallel hash table lookups. The input point division should therefore yield roughly equal-sized partitions for good load-balancing and also result in a small number of border vertices for fast merging. In this paper, we present a novel divide-step based on partitioning the triangulation of a small sample of the input points. In experiments on synthetic and real-world data sets, we achieve nearly perfectly balanced partitions and small border triangulations. This almost cuts running time in half compared to non-data-sensitive division schemes on inputs exhibiting an exploitable underlying structure.Comment: Short version submitted to EuroPar 201

Comment on Higgs Inflation and Naturalness

We rebut the recent claim (arXiv:0912.5463) that Einstein-frame scattering in the Higgs inflation model is unitary above the cut-off energy Lambda ~ Mp/xi. We show explicitly how unitarity problems arise in both the Einstein and Jordan frames of the theory. In a covariant gauge they arise from non-minimal Higgs self-couplings, which cannot be removed by field redefinitions because the target space is not flat. In unitary gauge, where there is only a single scalar which can be redefined to achieve canonical kinetic terms, the unitarity problems arise through non-minimal Higgs-gauge couplings.Comment: 5 pages, 1 figure V3: Journal Versio

Globular Cluster Distance Determinations

The present status of the distance scale to Galactic globular clusters is reviewed. Six distance determination techniques which are deemed to be most reliable are discussed in depth. These different techniques are used to calibrate the absolute magnitude of the RR Lyrae stars. The various calibrations fall into three groups. Main sequence fitting using Hipparcos parallaxes, theoretical HB models and the RR Lyrae in the LMC all favor a bright calibration, implying a `long' globular cluster distance scale. White dwarf fitting and the astrometric distances yield a somewhat fainter RR Lyrae calibration, while the statistical parallax solution yields faint RR Lyrae stars implying a `short' distance scale to globular clusters. Various secondary distance indicators discussed all favor the long distance scale. The `long' and `short' distance scales differ by (0.31+/-0.16) mag. Averaging together all of the different distance determinations yields Mv(RR) = (0.23+/-0.04)([Fe/H] + 1.6) + (0.56+/-0.12) mag.Comment: Invited review article to appear in: `Post-Hipparcos Cosmic Candles', A. Heck & F. Caputo (Eds), Kluwer Academic Publ., Dordrecht, in pres

Distances and ages of globular clusters using Hipparcos parallaxes of local subdwarfs

We discuss the impact of Population II and Globular Cluster (GCs) stars on the derivation of the age of the Universe, and on the study of the formation and early evolution of galaxies, our own in particular. The long-standing problem of the actual distance scale to Population II stars and GCs is addressed, and a variety of different methods commonly used to derive distances to Population II stars are briefly reviewed. Emphasis is given to the discussion of distances and ages for GCs derived using Hipparcos parallaxes of local subdwarfs. Results obtained by different authors are slightly different, depending on different assumptions about metallicity scale, reddenings, and corrections for undetected binaries. These and other uncertainties present in the method are discussed. Finally, we outline progress expected in the near future.Comment: Invited review article to appear in: `Post-Hipparcos Cosmic Candles', A. Heck & F. Caputo (Eds), Kluwer Academic Publ., Dordrecht, in press. 22 pages including 3 tables and 2 postscript figures, uses Kluwer's crckapb.sty LaTeX style file, enclose

Derivation of a high-resolution CT-based, semi-automated radiographic score in tuberculosis and its relationship to bacillary load and antitubercular therapy

Efforts to curb the tuberculosis (TB) pandemic remain hindered by a lack of objective measures to quantify disease severity and track treatment success that are valid in both HIV-1-infected and -uninfected TB patients. Ralph et al. [1] developed a promising radiographic scoring system, with baseline scores being predictive of sputum smear conversion at 2 months, but it is reliant on skilled readers and has not been systematically validated in predominantly HIV-infected study populations with varying CD4 counts. Superior to conventional chest radiography, high-resolution computed tomography (HRCT) is a highly sensitive tool to track endobronchial TB disease extent [2]

Random Matrix Theory and Chiral Symmetry in QCD

Random matrix theory is a powerful way to describe universal correlations of eigenvalues of complex systems. It also may serve as a schematic model for disorder in quantum systems. In this review, we discuss both types of applications of chiral random matrix theory to the QCD partition function. We show that constraints imposed by chiral symmetry and its spontaneous breaking determine the structure of low-energy effective partition functions for the Dirac spectrum. We thus derive exact results for the low-lying eigenvalues of the QCD Dirac operator. We argue that the statistical properties of these eigenvalues are universal and can be described by a random matrix theory with the global symmetries of the QCD partition function. The total number of such eigenvalues increases with the square root of the Euclidean four-volume. The spectral density for larger eigenvalues (but still well below a typical hadronic mass scale) also follows from the same low-energy effective partition function. The validity of the random matrix approach has been confirmed by many lattice QCD simulations in a wide parameter range. Stimulated by the success of the chiral random matrix theory in the description of universal properties of the Dirac eigenvalues, the random matrix model is extended to nonzero temperature and chemical potential. In this way we obtain qualitative results for the QCD phase diagram and the spectrum of the QCD Dirac operator. We discuss the nature of the quenched approximation and analyze quenched Dirac spectra at nonzero baryon density in terms of an effective partition function. Relations with other fields are also discussed.Comment: invited review article for Ann. Rev. Nucl. Part. Sci., 61 pages, 11 figures, uses ar.sty (included); references added and typos correcte

Association analysis of polymorphism in KIAA1717, HUMMLC2B, DECR1 and FTO genes with meat quality traits of the Berkshire breed

Single nucleotide polymorphisms (SNPs) in KIAA1717, HUMMLC2B, DECR1, and FTO genes have been found to be associated with some pork meat quality traits. In this study, we discovered that, in addition to meat quality traits reported previously, SNPs in these genes also are significantly associated with other meat quality traits in the Berkshire breed. A total of 323 Berkshire pigs bred under the same conditions were used for meat quality evaluation and polymerase chain reaction-amplified genes with restriction endonucleases (PCR-RFLP) genotyping analyses. The association analysis of RFLP genotyping with meat quality traits revealed that the SNPs in these 4 genes have novel associations with multiple meat quality traits (p < 0.01 or p < 0.05); a SNP in KIAA1717 was associated with meat color (CIE L), backfat thickness, drip loss, water-holding capacity, and pH24hr; a SNP in HUMMLC2B was associated with chemical composition (collagen), drip loss, shear force, and pH24hr; a SNP in DECR1 was associated with meat color (CIE a and b) and backfat thickness; and a SNP in FTO was associated with meat color (CIE L, a and b), protein content, drip loss, and water-holding capacity. Taken collectively, our results suggest that these 4 SNPs may be used for marker-assisted selection as a genetic marker for meat quality traits in Berkshire pigs.Key words: Berkshire, genetic markers, meat quality, SN

Search for electromagnetic properties of the neutrinos at the LHC

Exclusive production of neutrinos via photon-photon fusion provides an excellent opportunity to probe electromagnetic properties of the neutrinos at the LHC. We explore the potential of processes pp-> p gamma gamma p -> p nu anti-nu p and pp -> p gamma gamma p -> p nu anti-nu Z p to probe neutrino-photon and neutrino-two photon couplings. We show that these reactions provide more than seven orders of magnitude improvement in neutrino-two photon couplings compared to LEP limits.Comment: 11 pages, 4 tables, New backgrounds have been adde