Superluminal Vector in Ghost-free Massive Gravity

We present a classical analysis on the issue of vector superluminality in the decoupling limit ghost-free massive gravity with a Minkowski reference metric. We show explicitly in the Lorenz gauge that the theory is free of superluminal vector excitations around a nontrivial solution at the cubic order in the fields. In the same gauge, we demonstrate that superluminal vector modes arise at the quartic order and compute some superluminal propagating solutions. We then generalize our findings to all orders in a gauge-independent way. We check the physical consistency of the vector superluminalities, arguing that they are not physically detectable in the perturbation theory but could be trusted classically in the strong coupling region. Nevertheless, these superluminalities involve only low frequency group and phase velocities and are unable to determine the acausality of the theory.Comment: v2: references and clarifications added. v3: major revision, accepted for publication by JHE

Hyperfine interaction induced decoherence and deterministic teleportation of electrons in a quantum dot nanostructure

Recently, de Visser and Blaauboer [Phys. Rev. Lett. {\bf 96}, 246801 (2006)] proposed the most efficient deterministic teleportation protocol $\cal T$ for electron spins in a semiconductor nanostructure consisting of a single and a double quantum dot. However, it is as yet unknown if $\cal T$ can be completed before decoherence sets in. In this paper we analyze the detrimental effect of nuclear spin baths, the main source of decoherence, on $\cal T$. We show that nonclassical teleportation fidelity can be achieved with $\cal T$ provided certain conditions are met. Our study indicates that realization of quantum computation with quantum dots is indeed promising.Comment: 10 page

Effects of contusion load on cervical spinal cord:A finite element study

Injury of cervical spine is a common injury of locomotor system usually accompanied by spinal cord injury, however the injury mechanism of contusion load to the spinal cord is not clear. This study aims to investigate its injury mechanism associated with the contusion load, with different extents of spinal cord compression. A finite element model of cervical spinal cord was established and two scenarios of contusion injury loading conditions, i.e. back-to-front and front-to-back loads, were adopted. Four different compression displacements were applied to the middle section of the cervical spinal cord. The distributions of von Mises stress in middle transverse cross section were obtained from the finite element analysis. For the back-to-front loading scenario, the stress concentration was found in the area at and near the central canal and the damage may lead to the central canal syndrome from biomechanical point of view. With the front-to-back load, the maximum von Mises stress located in central canal area of gray matter when subject to 10% compression, whilst it appeared at the anterior horn when the compression increased. For the white matter, the maximum von Mises stress appeared in the area of the anterior funiculus. This leads to complicated symptoms given rise by damage to multiple locations in the cervical spinal cord. The illustrative results demonstrated the need of considering different loading scenarios in understanding the damage mechanisms of the cervical spinal cord, particularly when the loading conditions were given rise by different pathophysiological causes

Multicenter Phase II Trial of the WEE1 Inhibitor Adavosertib in Refractory Solid Tumors Harboring

PURPOSE: Preclinical cancer models harboring PATIENTS AND METHODS: Patients aged ≥ 18 years with measurable disease and refractory solid tumors harboring RESULTS: Thirty patients were enrolled. The median follow-up duration was 9.9 months. Eight patients had partial responses (PRs), and three had stable disease (SD) ≥ 6 months, with an ORR of 27% (95% CI, 12 to 46), a SD ≥ 6 months/PR rate of 37% (95% CI, 20 to 56), a median progression-free survival duration of 4.1 months (95% CI, 1.8 to 6.4), and a median overall survival duration of 9.9 months (95% CI, 4.8 to 15). Fourteen patients with epithelial ovarian cancer showed an ORR of 36% (95% CI, 13 to 65) and SD ≥ 6 months/PR of 57% (95% CI, 29 to 82), a median progression-free survival duration of 6.3 months (95% CI, 2.4 to 10.2), and a median overall survival duration of 14.9 months (95% CI, 8.9 to 20.9). Common treatment-related toxicities were GI, hematologic toxicities, and fatigue. CONCLUSION: Adavosertib monotherapy demonstrates a manageable toxicity profile and promising clinical activity in refractory solid tumors harborin

Nonlocal Galileons and self-acceleration

A certain class of nonlocal theories eliminates an arbitrary cosmological constant (CC) from a universe that can be perceived as our world. Dark energy then cannot be explained by a CC; it could however be due to massive gravity. We calculate the new corrections, which originate from the nonlocal terms that eliminate the CC, to the decoupling limit Lagrangian of massive gravity. The new nonlocal terms also have internal field space Galilean symmetry and are referred here as “nonlocal Galileons.” We then study a self-accelerated solution and show that the new nonlocal terms change the perturbative stability analysis. In particular, small fluctuations are now stable and non-superluminal for some simple parameter choices, whereas for the same choices the pure massive gravity fluctuations are unstable. We also study stable spherically symmetric solutions on this background

Research of Variable Application Control System Based on Fuzzy Control

The AT89C52 microcontroller and the fuzzy control algorithm is used to design the automatic control system of variable Spraying pesticides. The system adjusts automatically the electric regulating valve according to given Spraying pesticides per unit area so that the actual amount of Spraying pesticides equal to the set value. The simulation model of automatic control system of variable pesticide application was established, and the controller was simulated by MATLAB / SIMULINK software fuzzy control toolbox. The simulation results show that the structure and algorithm of the proposed automatic control system of pesticide application is feasible, The system improves greatly pesticide utilization, reduce pesticide residues and environmental pollution

Co-Diffusion of Mobile Operator’s OTT and SMS Messaging Services in Emerging Economies

The debate about the relationship between the Over the Top (OTT) messaging service and the Short Message Service (SMS) has received intensive attention in emerging economies. In this study we attempt to explore the diffusion and co-diffusion processes of OTT and SMS messaging services that are integrated in one product, in particular China Mobile Fetion. We employ the niche theory and media synchronicity theory as foundations for the development and explanation of diffusion-based hypotheses. We adapt an extended Bass model to inscribe the dynamics of the service co-diffusion and use the empirical data of Fetion to test the hypotheses. Our results show that Fetion OTT messaging service diffuses much faster than Fetion SMS messaging service. More importantly, our analysis reveals the complementary relationship between the two Fetion messaging services in its early stage of diffusion, which contradicts to wide-held substitutive standpoint. Plausible reasons and implications of this study are discussed