A note on spacelike and timelike compactness

When studying the causal propagation of a field in a globally hyperbolic spacetime M, one often wants to express the physical intuition that it has compact support in spacelike directions, or that its support is a spacelike compact set. We compare a number of logically distinct formulations of this idea, and of the complementary idea of timelike compactness, and we clarify their interrelations. E.g., a closed subset A of M has a compact intersection with all Cauchy surfaces if and only if A is contained in J(K) for some compact set K. (However, it does not suffice to consider only those Cauchy surfaces that partake in a given foliation of M.) Similarly, a closed subset A of M is contained in a region between two Cauchy surfaces if and only if the intersection of A with J(K) is compact for all compact K. We also treat future and past compact sets in a similar way

Search for ηc′\eta_{c}^{'} and hc(1P1)h_{c} (^{1}P_{1}) states in the e+e−e^+ e^- annihilations

Productions and decays of spin-singlet $S,P-$wave charmonium states, $\eta_{c}^{'}$ and $h_{c} (^{1}P_{1})$, in the $e^+ e^-$ annihilations are considered in the QCD multipole expansion with neglecting nonlocality in time coming from the color-octet intermediate states. Our approximation is opposite to the Kuang-Yan's model. The results are $B (\psi^{'} \rightarrow h_{c} + \pi^{0}) \approx 0.3 \%$, $B ( \psi^{'} \rightarrow \eta^{'} + \gamma ) \approx 0.34 \%$, $\Gamma (\eta_{c}^{'} \rightarrow J/\psi + \gamma) \approx 0.26$ keV and $\Gamma (h_{c} \rightarrow J/\psi + \pi^{0}) \approx 2.5$ keV.Comment: LaTeX file, to appear in Phys. Rev.

Problems of Double Charm Production in e+e−e^+e^- Annihilation at s=10.6\sqrt{s}=10.6 GeV

Using the nonrelativistic QCD(NRQCD) factorization formalism, we calculate the color-singlet cross sections for exclusive production processes ${e^++e^-\to J/\psi+\eta_c}$~ and ~$e^++e^-\to J/\psi + \chi_{cJ}$~$(J=0,1,2)$ at the center-of-mass energy $\sqrt{s}$=10.6 GeV. The cross sections are estimated to be 5.5fb, 6.7fb, 1.1fb, and 1.6fb for $\eta_c, \chi_{c0}, \chi_{c1}$ and $\chi_{c2}$, respectively. The calculated $J/\psi+\eta_c$ production rate is smaller than the recent Belle data by about an order of magnitude, which might indicate the failure of perturbative QCD calculation to explain the double-charmonium production data. The complete $\cal{O}$$(\alpha^2_{s})$ color-singlet cross section for ${e^++e^-\to \chi_{c0}+ c\bar {c}}$ is calculated. In addition, we also evaluate the ratio of exclusive to inclusive production cross sections. The ratio of $J/\psi\eta_c$ production to $J/\psi c\bar{c}$ production could be consistent with the experimental data.Comment: 10 pages, 4 figures. A few references added, errors and typoes correcte

Sestrin2 promotes LKB1‐mediated AMPK activation in the ischemic heart

The regulation of AMPK in the ischemic heart remains incompletely understood. Recent evidence implicates the role of Sestrin2 in the AMPK signaling pathway, and it is hypothesized that Sestrin2 plays an influential role during myocardial ischemia to promote AMPK activation. Sestrin2 protein was found to be expressed in adult cardiomyocytes and accumulated in the heart during ischemic conditions. Sestrin2 knockout (KO) mice were used to determine the importance of Sestrin2 during ischemia and reperfusion (I/R) injury. When wild‐type (WT) and Sestrin2 KO mice were subjected to in vivo I/R, myocardial infarct size was significantly greater in Sestrin2 KO compared with WT hearts. Similarly, Langendorff perfused hearts indicated exacerbated postischemic contractile function in Sestrin2 KO hearts compared with WT. Ischemic AMPK activation was found to be impaired in the Sestrin2 KO hearts. Immunoprecipitation of Sestrin2 demonstrated an association with AMPK. Moreover, liver kinase B1 (LKB1), a major AMPK upstream kinase, was associated with the Sestrin2‐AMPK complex in a time‐dependent manner during ischemia, whereas this interaction was nearly abolished in Sestrin2 KO hearts. Thus, Sestrin2 plays an important role in cardioprotection against I/R injury, serving as an LKB1‐AMPK scaffold to initiate AMPK activation during ischemic insults.—Morrison, A., Chen, L. Wang, J., Zhang, M., Yang, H., Ma, Y., Budanov, A., Lee, J. H., Karin, M., Li, J. Sestrin2 promotes LKB1‐mediated AMPK activation in the ischemic heart. FASEB J. 29, 408‐417 (2015). www.fasebj.orgPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154534/1/fsb2fj14258814-sup-0001.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154534/2/fsb2fj14258814.pd

Boston University Jazz Fest, February 23, 1983

This is the concert program of Boston University Jazz Fest performance on Wednesday, February 23, 1983 at 8:00 p.m., at the Concert Hall, 855 Commonwealth Avenue. Works performed were Long Yellow Road by Toshiko Akiyoshi, El Gato by John Berry, Louisiana by J. C. Johnson (arr. by Rob McConnell), The Heat's On by Sammy Nestico, 42nd and Broadway by Jerry Mulligan, This Plum is Too Ripe by Schmidt/Jones (arr. by Paul Siskind), 500 Miles High by Chick Korea (arr. Neil Slater), Dirge-Stomp by Billy Strayhorn (arr. by Jeff Friedman), Exemption by Teese Gohl, How My Heart Sings by Earl Zindars (arr. Herb Pomeroy), Ko Ko by Duke Ellington (arr. Jeff Friedman, Eastwards by Tiger Okoshi, Sweet Willie by Phil Woods, After the Rain by Sammy Nestico, Alcazar by Don Sebesky, and Mr. P. C. by John Coltrane (arr. by Hank Wiktorowicz). Digitization for Boston University Concert Programs was supported by the Boston University Humanities Library Endowed Fund

Hopf algebra structure on topological Hochschild homology

The topological Hochschild homology THH(R) of a commutative S-algebra (E_infty ring spectrum) R naturally has the structure of a commutative R-algebra in the strict sense, and of a Hopf algebra over R in the homotopy category. We show, under a flatness assumption, that this makes the Boekstedt spectral sequence converging to the mod p homology of THH(R) into a Hopf algebra spectral sequence. We then apply this additional structure to the study of some interesting examples, including the commutative S-algebras ku, ko, tmf, ju and j, and to calculate the homotopy groups of THH(ku) and THH(ko) after smashing with suitable finite complexes. This is part of a program to make systematic computations of the algebraic K-theory of S-algebras, by means of the cyclotomic trace map to topological cyclic homology.Comment: Published by Algebraic and Geometric Topology at http://www.maths.warwick.ac.uk/agt/AGTVol5/agt-5-49.abs.htm

The Kappa in J/Psi -> Kpplus-piminus-Kminus-piplus

BES II data for J/Psi->K*(890)Kpi reveal a strong kappa peak in the Kpi S-wave near threshold. Both magnitude and phase are determined in slices of Kpi mass by interferences with strong Ko(1430), K1(1270) and K1(1400) signals. The phase variation with mass agrees within errors with LASS data for Kpi elastic scattering. A combined fit is presented to both BES and LASS data. The fit uses a Breit-Wigner amplitude with an s-dependent width containing an Adler zero. The kappa pole is at 760+-20(stat)+-40(syst) - i(420+-45+-60syst) MeV. The S-wave I=0 scattering length a_0 = 0.23+-0.04 (in units of m(pi)) is close to the prediction 0.19+-0.02 of Chiral Perturbation Theory.Comment: 20 pages, 5 figure

Kinematic Effects in Quarkonia Production

We investigate energy (momentum) distributions in J/Psi photoproduction and J/Psi production in B meson decay. In particular the upper endpoint region of the spectrum is examined where the effect of soft gluon emission from the ccbar pair becomes important. Constructing a model which is consistent with the so-called shape function formalism we consider these fragmentation effects and show that the relevance of possible colour octet contributions in the photoproduction channel is still inconclusive.Comment: LaTeX, 7 pages, 3 figures, The complete paper is also available via the www at http://www-ttp.physik.uni-karlsruhe.de/Preprints