Second-Order Formalism for 3D Spin-3 Gravity

A second-order formalism for the theory of 3D spin-3 gravity is considered. Such a formalism is obtained by solving the torsion-free condition for the spin connection \omega^a_{\mu}, and substituting the result into the action integral. In the first-order formalism of the spin-3 gravity defined in terms of SL(3,R) X SL(3,R) Chern-Simons (CS) theory, however, the generalized torsion-free condition cannot be easily solved for the spin connection, because the vielbein e^a_{\mu} itself is not invertible. To circumvent this problem, extra vielbein-like fields e^a_{\mu\nu} are introduced as a functional of e^a_{\mu}. New set of affine-like connections \Gamma_{\mu M}^N are defined in terms of the metric-like fields, and a generalization of the Riemann curvature tensor is also presented. In terms of this generalized Riemann tensor the action integral in the second-order formalism is expressed. The transformation rules of the metric and the spin-3 gauge field under the generalized diffeomorphims are obtained explicitly. As in Einstein gravity, the new affine-like connections are related to the spin connection by a certain gauge transformation, and a gravitational CS term expressed in terms of the new connections is also presented.Comment: 40 pages, no figures. v2:references added, coefficients of eqs in apppendix D corrected, minor typos also corrected, v3:Version accepted for publication in Classical and Quantum Gravit

Some Remarks on Theories with Large Compact Dimensions and TeV-Scale Quantum Gravity

We comment on some implications of theories with large compactification radii and TeV-scale quantum gravity. These include the behavior of high-energy gravitational scattering cross sections and consequences for ultra-high-energy cosmic rays and neutrino scattering, the question of how to generate naturally light neutrino masses, the issue of quark-lepton unification, the equivalence principle, and the cosmological constant.Comment: 28 pages, Late

A Pro-Cathepsin L Mutant Is a Luminal Substrate for Endoplasmic-Reticulum-Associated Degradation in C. elegans

Endoplasmic-reticulum associated degradation (ERAD) is a major cellular misfolded protein disposal pathway that is well conserved from yeast to mammals. In yeast, a mutant of carboxypeptidase Y (CPY*) was found to be a luminal ER substrate and has served as a useful marker to help identify modifiers of the ERAD pathway. Due to its ease of genetic manipulation and the ability to conduct a genome wide screen for modifiers of molecular pathways, C. elegans has become one of the preferred metazoans for studying cell biological processes, such as ERAD. However, a marker of ERAD activity comparable to CPY* has not been developed for this model system. We describe a mutant of pro-cathepsin L fused to YFP that no longer targets to the lysosome, but is efficiently eliminated by the ERAD pathway. Using this mutant pro-cathepsin L, we found that components of the mammalian ERAD system that participate in the degradation of ER luminal substrates were conserved in C. elegans. This transgenic line will facilitate high-throughput genetic or pharmacological screens for ERAD modifiers using widefield epifluorescence microscopy

Protein quality control: the who’s who, the where’s and therapeutic escapes

In cells the quality of newly synthesized proteins is monitored in regard to proper folding and correct assembly in the early secretory pathway, the cytosol and the nucleoplasm. Proteins recognized as non-native in the ER will be removed and degraded by a process termed ERAD. ERAD of aberrant proteins is accompanied by various changes of cellular organelles and results in protein folding diseases. This review focuses on how the immunocytochemical labeling and electron microscopic analyses have helped to disclose the in situ subcellular distribution pattern of some of the key machinery proteins of the cellular protein quality control, the organelle changes due to the presence of misfolded proteins, and the efficiency of synthetic chaperones to rescue disease-causing trafficking defects of aberrant proteins

OBSERVATIONS OF FROND GROWTH AND DEVELOPMENT IN PENTAGRAMMA TRIANGULARIS SUBSP. TRIANGULARIS (PTERIDACEAE) OF SOUTHERN CALIFORNIA

Volume: 53Start Page: 60End Page: 6

ASPECTS OF REPRODUCTIVE BIOLOGY IN THE SEXUALLY DIMORPHIC SHRUB MALOSMA LAURINA (ANACARDIACEAE)

Volume: 51Start Page: 293End Page: 30

Reproductive Response to Fire by the Laurel Sumac, Malosma laurina (Anacardiaceae)

Volume: 44Start Page: 300End Page: 30