U(1)_R mediation from the flux compactification in six dimensions

We consider a supersymmetric completion of codimension-two branes with nonzero tension in a 6D gauged supergravity. As a consequence, we obtain the football solution with 4D Minkowski space as a new supersymmetric background that preserves 4D N=1 SUSY. In the presence of brane multiplets, we derive the 4D effective supergravity action for the football background and show that the remaining modulus can be stabilized by a bulk non-perturbative correction with brane uplifting potentials at a zero vacuum energy. We find that the U(1)_R mediation can be a dominant source of SUSY breaking for a brane scalar with nonzero R charge.Comment: 3 pages, no figures, to appear in the proceedings of the 16th International Conference on Supersymmetry and the Unification of Fundamental Interactions (SUSY-2008), Seoul, Korea, 16-21 June, 200

Machine Learning-Aided Cooperative Localization under Dense Urban Environment

Future wireless network technology provides automobiles with the connectivity feature to consolidate the concept of vehicular networks that collaborate on conducting cooperative driving tasks. The full potential of connected vehicles, which promises road safety and quality driving experience, can be leveraged if machine learning models guarantee the robustness in performing core functions including localization and controls. Location awareness, in particular, lends itself to the deployment of location-specific services and the improvement of the operation performance. The localization entails direct communication to the network infrastructure, and the resulting centralized positioning solutions readily become intractable as the network scales up. As an alternative to the centralized solutions, this article addresses decentralized principle of vehicular localization reinforced by machine learning techniques in dense urban environments with frequent inaccessibility to reliable measurement. As such, the collaboration of multiple vehicles enhances the positioning performance of machine learning approaches. A virtual testbed is developed to validate this machine learning model for real-map vehicular networks. Numerical results demonstrate universal feasibility of cooperative localization, in particular, for dense urban area configurations

Instanton effects on electromagnetic transitions of charmonia

We investigate the mass spectrum and electromagnetic transitions of charmonia, emphasizing the instanton effects on them. The heavy-quark potential consists of the Coulomb-like potential from one-gluon exchange and the linear confining potential. We introduce the nonperturbative heavy-quark potential derived from the instanton vacuum. We also consider the screened confining potential, which better describes the electromagnetic decays of higher excited states. Using this improved heavy-quark potential, we compute the mass spectrum and electromagnetic decays of the charmonia. Focusing on the instanton effects, we discuss the results compared with the experimental data and those from other works. The instanton effects are marginal on the electromagnetic decays of charmonia.Comment: 10 pages and 4 figures. The final version to be published in Progress of Theoretical and Experimental Physic

Two-dimensional charge distributions of the Δ\Delta baryon: Interpolation between the nonrelativistic and ultrarelativistic limit

We investigate how the charge distributions of both the unpolarized and transversely polarized $\Delta$ baryon change as the longitudinal momentum~($P_{z}$) of the $\Delta$ baryon increases from $P_{z}=0$ to $P_{z}=\infty$ in a Wigner phase-space perspective. When the $\Delta$ baryon is longitudinally polarized, its two-dimensional charge distribution is kept to be spherically symmetric with $P_{z}$ varied, whereas when the $\Delta$ baryon is transversely polarized along the $x$-axis, the quadrupole contribution emerges at the rest frame ($P_{z}=0$). When $P_{z}$ grows, the electric dipole and octupole moments are induced. The induced dipole moment dominates over other higher multipole contributions and governs the deformation of the charge distribution of the $\Delta$ baryon.Comment: 22 pages, 12 figure

The Mechanism of Copperâ Catalyzed Trifunctionalization of Terminal Allenes

A highly selective copperâ catalyzed trifunctionalization of allenes has been established based on diborylation/cyanation with bis(pinacolato)diboron (B2pin2) and Nâ cyanoâ Nâ phenylâ pâ toluenesulfonamide (NCTS). The Cuâ catalyzed trifunctionalization of terminal allenes is composed of three catalytic reactions (first borocupration, electrophilic cyanation, and second borocupration) that provide a densely functionalized product with regioâ , chemoâ and diastereoselectivity. Allene substrates have multiple reactionâ sites, and the selectivities are determined by the suitable interactions (e.g., electronic and steric demands) between the catalyst and substrates. We employed DFT calculations to understand the cascade copperâ catalyzed trifunctionalization of terminal allenes, providing denselyâ functionalized organic molecules with outstanding regioâ , chemoâ and diastereoselectivity in high yields. The selectivity challenges presented by cumulated Ï â systems are addressed by systematic computational studies; these give insight to the catalytic multipleâ functionalization strategies and explain the high selectivities that we see for these reactions.Cuâ catalyzed trifunctionalization of terminal allenes, through three catalytic reactions (borocupration, electrophilic cyanation, followed by a second borocupration), provides a densely functionalized product with regioâ , chemoâ and diastereoselectivity (see figure). Density functional theory calculations help to understand the cascade catalytic mechanism.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/150512/1/chem201900673.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150512/2/chem201900673-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150512/3/chem201900673_am.pd

The Mechanism of Copperâ Catalyzed Trifunctionalization of Terminal Allenes

A highly selective copperâ catalyzed trifunctionalization of allenes has been established based on diborylation/cyanation with bis(pinacolato)diboron (B2pin2) and Nâ cyanoâ Nâ phenylâ pâ toluenesulfonamide (NCTS). The Cuâ catalyzed trifunctionalization of terminal allenes is composed of three catalytic reactions (first borocupration, electrophilic cyanation, and second borocupration) that provide a densely functionalized product with regioâ , chemoâ and diastereoselectivity. Allene substrates have multiple reactionâ sites, and the selectivities are determined by the suitable interactions (e.g., electronic and steric demands) between the catalyst and substrates. We employed DFT calculations to understand the cascade copperâ catalyzed trifunctionalization of terminal allenes, providing denselyâ functionalized organic molecules with outstanding regioâ , chemoâ and diastereoselectivity in high yields. The selectivity challenges presented by cumulated Ï â systems are addressed by systematic computational studies; these give insight to the catalytic multipleâ functionalization strategies and explain the high selectivities that we see for these reactions.Cuâ catalyzed trifunctionalization of terminal allenes, through three catalytic reactions (borocupration, electrophilic cyanation, followed by a second borocupration), provides a densely functionalized product with regioâ , chemoâ and diastereoselectivity (see figure). Density functional theory calculations help to understand the cascade catalytic mechanism.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/150512/1/chem201900673.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150512/2/chem201900673-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150512/3/chem201900673_am.pd

Electromagnet Weight Reduction in a Magnetic Levitation System for Contactless Delivery Applications

This paper presents an optimum design of a lightweight vehicle levitation electromagnet, which also provides a passive guide force in a magnetic levitation system for contactless delivery applications. The split alignment of C-shaped electromagnets about C-shaped rails has a bad effect on the lateral deviation force, therefore, no-split positioning of electromagnets is better for lateral performance. This is verified by simulations and experiments. This paper presents a statistically optimized design with a high number of the design variables to reduce the weight of the electromagnet under the constraint of normal force using response surface methodology (RSM) and the kriging interpolation method. 2D and 3D magnetostatic analysis of the electromagnet are performed using ANSYS. The most effective design variables are extracted by a Pareto chart. The most desirable set is determined and the influence of each design variable on the objective function can be obtained. The generalized reduced gradient (GRG) algorithm is adopted in the kriging model. This paper’s procedure is validated by a comparison between experimental and calculation results, which shows that the predicted performance of the electromagnet designed by RSM is in good agreement with the simulation results

Posterior Trans-Dural Repair of Iatrogenic Spinal Cord Herniation after Resection of Ossification of Posterior Longitudinal Ligament

Iatrogenic spinal cord herniation is a rare complication following spinal surgery. We introduce a posterior trans-dural repair technique used in a case of thoracic spinal cord herniation through a ventral dural defect following resection of ossification of the posterior longitudinal ligament (OPLL) in the cervicothoracic spine. A 51-year-old female was suffering from paraplegia after laminectomy alone for cervicothoracic OPLL. Magnetic resonance imaging revealed a severely compressed spinal cord with pseudomeningocele identified postoperatively. Cerebrospinal fluid leak and iatrogenic spinal cord herniation persisted despite several operations with duroplasty and sealing agent. Finally, the problems were treated by repair of the ventral dural defect with posterior trans-dural duroplasty. Several months after surgery, the patient could walk independently. This surgical technique can be applied to treat ventral dural defect and spinal cord herniation